# Gravitation and Newton s Synthesis

Size: px
Start display at page:

Transcription

1 Gravitation and Newton s Synthesis Vocabulary law of unviversal Kepler s laws of planetary perturbations casual laws gravitation motion casuality field graviational field inertial mass gravitational mass principle of equivalence black hole 6-1 Newton s Law of Universal Gravitation Whenever a body has a force exerted on it, that force is exerted by some other body what exerts the force of gravity Newton concluded that it must be the earth itself that exerts the gravitational force on objects at its surface At the surface of the Earth, the force of gravity accelerates objects at 9.80 m/s^2 What about the moon? You could determine the a based on the concept of centripetal acceleration You would discover that the acceleration of the Moon toward the Earth is 1/3600 as great as the acceleration of objects at the Earth s surface Newton concluded that the gravitational force exerted by the Earth on any object decreases with the square of its distance r from the Earth s center Equation Box 6-1 Newton realized that the force of gravity on an object depends not only on distance but also on the object s mass In fact it is directly proportional to its mass Newtons third law- Earth exerts a force and the moon exerts a force on the Earth Because of the symmetry, Newton argued that the force of gravity must be proportional to both the masses Equation Box 6-2 Newton went a step further in his analysis of gravity 1 RoessBoss

2 He concluded based on the orbits of the planets that the force required to hold the different planets in orbit around the sun seems to diminish as the inverse square of their distance from the sun This led him to believe that it is also the gravitational force that acts between the Sun and each of the planets to keep them in their orbits And if gravity acts between these objects, why not in all Law of Universal gravitation- every particle in the universe attracts every other particle with a force that is proportional to the product of their masses and inversely proportional to the square of the distance between them. This force acts along the line joining the two particles The magnitude of the gravitational force can be written as Equation Box 6-3 G is the universal constant which must be measured experimentally and has the same numerical value for all objects The value os G must be very small, since we are not aware of any force of attraction between ordinary sized objects such as two baseballs The force was measured 100 years after Newton by Henry Cavendish in 1798 to detect and measure the incredibly small force, he used an apparatus with two masses on a string hanging from a rod which was hanging from another string He determined G to be 6.67 E -11 N m^2/ kg^2 usually r will be measured from the center, but some objects make it very hard to see that With two spheres that are uniform in shape the correct place to measure is from the center When dealing with particle- one has to use calculus 6-2 Vector Form of Newton s Law of Universal Gravitation Since you are dealing with a force you can still use the vector rules in determining resultants when you have various directions involved. It is also helpful when you have many particles involved 6-3 Gravity Near the Earth's Surface; Geophysical Applications Now lets look at the relationship between weight and Universal Gravity Law 2 RoessBoss

3 Equation Box 6-4 Thus the acceleration of gravity at the surface of the Earth is determined by the mass of the earth and the radius of the earth Once G was determined then we could determine g When you do the math you discover that g is 9.80 m/s^2 You can also determine the mass of the Earth which is 5.98 E24 Kg Keep in mind that g changes based on location because Earth is not a perfect sphere The higher you are the less g is Generally we use 9.80 since it is a good round about estimate overall Geophysicists use the value of g and how it changes based on the Earth s crust in order to determine where mineral deposits are, salt domes, oil, and other resources 6-4 Satellites and Weightlessness Artificial satellites circling the Earth are commonplace A satellite is placed in orbit by accelerating it to a sufficiently high tangential speed with the use of rockets If the speed it too high, the spacecraft will not be confined to Earth s gravity and will escape, never to return If the speed is too low, it will return to Earth Satellites are usually put into circular orbits because they require the least takeoff speed If a satellite stopped moving it would fall back to earth At high speed it would fly into space Earth s gravitational force pulls it into orbit A satellite is actually falling but it has high tangential speed which keeps it from hitting earth For satellites that move in circles, the needed acceleration is v^2/r The force that gives a satellite this acceleration is the force of gravity and since a satellite may be at a considerable distance from the earth- we must use the equation for the force acting on it Equation Box RoessBoss

4 Note that only one force- gravity- is acting on the satellite and that r is the sum of the Earth s radius plus the satellites height h above the earth People and other objects in a satellite circling the Earth are said to experience weightlessness You can feel this in an elevator If you dropped a pencil in an elevator that was falling- the pencil would be falling with acceleration g but so would the floor of the elevator and the person The pencil would hover in-front of the person- apparent weightlessness- because in fact gravity is still acting on the object and the weight is still mg It is only weightless in that it is in free fall Prolong effects of weightlessness can have adverse effects on the human body like diminished blood cells, bone structure etc 6-5 Kepler s Law and Newton s Synthesis Johannes Kepler describes the motion of the planets about the sun Kepler used Tycho Brahe s data of mars to derive these laws Keplers laws of planetary motion o First Law- The path of each planet about the sun is an ellipse with the sun at one focus o Second Law- Each planet moves so that an imaginary line drawn from the sun to the planet sweeps out equal areas in equal periods of time o Third Law- the ratio of the squares of the periods of any two planets revolving about the sun is equal to the ratio of the cubes of their semimajor axes (the semimajor axes is half the long axis of the orbit and represents the planets average distance from the sun) That is if T1 and T2 represent the periods for any two planets and s1 and s2 represents the semi major axes then Equation Box 6-6 The s^3/t^2 are the same for each planet Planetary data applied to Keplerʼs Third Law Planet Average Distance from sun, s (10^6) Period T (Earth Years) s^3/t^2 (10^24 km^3/y^2) Mercury Venus 4 RoessBoss

5 Planetary data applied to Keplerʼs Third Law Earth Mars Jupiter Saturn Uranus Neptune Pluto Kepler arrived at his laws through careful analysis of experimental data Newton showed that keplers laws could be derived mathematically from the law of universal gravitation and the laws of motion He also showed that for any reasonable form for the gravitational force law, only one that depends on the inverse square of the distance is fully consistent with Kepler s law He thus used Keplers laws as evidence in favor of his law of universal gravitation If you go through the work you will arrive at a relationship between Keplers and Newtons which is based on the period and the radius Equation Box 6-7 This is also another interpretation of Kepler s third law You can not compare Earth-Moon to Sun-Mars... The gravity attraction is based on separate things Measurements on the orbits of the planets indicated that they did not precisely follow Kepler s laws there are slight deviations from perfectly elliptical orbits This is due to bodies interacting with one another as they go through their orbit But because of these small forces each planetary orbit should depart from a perfectly ellipse orbit- these deviations are perturbations These perturbations also have lead to the discovery of other planets like Neptune and pluto Planets around other stars also wobble The laws formulated by Newton are referred to as casual laws Causality means the idea that one occurrence can cause another 5 RoessBoss

6 6-6 Gravitational Field most of the forces we meet in everyday life are contact forces- push or pull on a lawn mower etc gravitational force acts over a distance- there is a force even when the two objects are not in contact The idea of a force acting at a distance was a difficult one for early thinkers- Newton himself felt uneasy with this concept when he published his law Another point of view that avoids some of these conceptual difficulties is the concept of the field- developed by Michael Faraday to aid in the understanding of the electromagnetism Later on it was applied to gravity According to the field concept a gravitational field surrounds every body that has mass and this field permeates all of space A second body at a particular location near the first body experiences a force because of the gravitational mass is considered to act directly on this mass (we are closer to the idea of a contact force) We can quantitatively define the gravitational field as the gravitational force per unit mass at any point in space If we want to measure the gravitational field at any point- we place a small test mass m at that point and measure the force exerted on it Equation Box 6-8 The units of g are N/kg It is clear that the gravitational field which an object experiences has magnitude equal to the acceleration due to gravity at that point 1 N = 1 kg m/s^2- which is why we use the units m/s^2 6-7 Types of Forces in Nature Newton s law of universal gravitation depends on the distance between the masses of the objects involved Newtons second law on the other hand tells how a body will accelerate due to any type of force in the twentieth century physicist came to recognize four different fundamental forces in nature o the gravitational force o the electromagnetic force o the strong nuclear force o weak nuclear force 6 RoessBoss

7 Physicists have been working on theories that would unify these four forces- that is to consider some or all of these forces as different manifestations Electromagnetic and weak nuclear forces have been theoretically united to form successful electroweak theory in which the electromagnetic and weak forces are seen as two different manifestations of a single electroweak force Attempts to further unify the forces such as grand united theories are hot topics currently ordinary forces fit into the electromagnetic forces 6-8 Gravitational Versus Inertial Mass; the principle of equivalence Newton s second law relates the force acting on a body to its acceleration and its inertial mass as we call it Inertial mass- represents a resistance to any force we have dealt with mass as a property related to the gravitational force- that is mass as a quantity that determines the strength of a gravitational force between two bodies- gravitational mass Newtons and Cavendish s experiments indicated that these two types of mass are equal for a body and modern experiments have confirmed it The equivalence between gravitational and inertial masses was raised by Albert Einstein to a principle of nature Einstein called it simply the principle of equivalence He used it for his foundation for his general theory of relativity There is no experiment observers can perform to distinguish if an acceleration arises because of gravitational force or because their reference frame is accelerating How the body reacts to inertia or gravity is indistinguishable 6-9 Gravitation as Curvature of Space; Black Holes The principle of equivalence can be used to show that light ought to be deflected due to gravitational force of a massive body consider an elevator in free space where no gravity acts on it If there is a hole in the side of the elevator and a beam of light enters from outside, the beam travels straight across the elevator and makes a spot on the opposite side if the elevator is at rest If the elevator is accelerating upward then the beam still travels straight However our frame of reference since the elevator is moving it appears that the light has bent According to the equivalence principle an upward accelerating reference frame is equivalent to a downward gravitational field So we expect gravity to exert a force on a beam of light and to bend it out of a straight line Einstein in his general theory of relativity predicted that- light would be affected by gravity 7 RoessBoss

8 It was calculated that light from a distant star would be deflected by 1.75 of arc as it passes near the sun Such a deflection was measured in 1919 during an eclipse of the sun The eclipse reduced the brightness of the sun so that the stars in line with its edge at that moment would be visible A light beam travels the most direct path between two points If a light beam can follow a curved path then the curved path must be the shortest distance between two points Thus space must be curved and that it is the gravitational field that causes the curvature The curvature is greatest near very massive bodies The extreme curvature of space time could be produced by a black hole black hole is a hugely massive star that is so dense and so massive that gravity would be so strong that even light could not escape it Light would be pulled back in by the force of gravity since no light escapes it- it is black A body might pass by it and be deflected by its gravitational field, but if the body came too close, it would be swallowed up never to escape one theory is that there is a giant black hole in the center of our universe 8 RoessBoss

### Newton s Law of Universal Gravitation

Newton s Law of Universal Gravitation The greatest moments in science are when two phenomena that were considered completely separate suddenly are seen as just two different versions of the same thing.

### Name Class Date. true

Exercises 131 The Falling Apple (page 233) 1 Describe the legend of Newton s discovery that gravity extends throughout the universe According to legend, Newton saw an apple fall from a tree and realized

### Notes: Most of the material in this chapter is taken from Young and Freedman, Chap. 13.

Chapter 5. Gravitation Notes: Most of the material in this chapter is taken from Young and Freedman, Chap. 13. 5.1 Newton s Law of Gravitation We have already studied the effects of gravity through the

### Halliday, Resnick & Walker Chapter 13. Gravitation. Physics 1A PHYS1121 Professor Michael Burton

Halliday, Resnick & Walker Chapter 13 Gravitation Physics 1A PHYS1121 Professor Michael Burton II_A2: Planetary Orbits in the Solar System + Galaxy Interactions (You Tube) 21 seconds 13-1 Newton's Law

### Halliday, Resnick & Walker Chapter 13. Gravitation. Physics 1A PHYS1121 Professor Michael Burton

Halliday, Resnick & Walker Chapter 13 Gravitation Physics 1A PHYS1121 Professor Michael Burton II_A2: Planetary Orbits in the Solar System + Galaxy Interactions (You Tube) 21 seconds 13-1 Newton's Law

### From Aristotle to Newton

From Aristotle to Newton The history of the Solar System (and the universe to some extent) from ancient Greek times through to the beginnings of modern physics. The Geocentric Model Ancient Greek astronomers

### Lecture 13. Gravity in the Solar System

Lecture 13 Gravity in the Solar System Guiding Questions 1. How was the heliocentric model established? What are monumental steps in the history of the heliocentric model? 2. How do Kepler s three laws

### circular motion & gravitation physics 111N

circular motion & gravitation physics 111N uniform circular motion an object moving around a circle at a constant rate must have an acceleration always perpendicular to the velocity (else the speed would

### USING MS EXCEL FOR DATA ANALYSIS AND SIMULATION

USING MS EXCEL FOR DATA ANALYSIS AND SIMULATION Ian Cooper School of Physics The University of Sydney i.cooper@physics.usyd.edu.au Introduction The numerical calculations performed by scientists and engineers

### Name: Date: Period: Gravity Study Guide

Vocabulary: Define the following terms. Law of Universal Gravitation Gravity Study Guide Weight Weightlessness Gravitational Field Black hole Escape velocity Math: Be able to use the equation for the law

### GRAVITATIONAL FIELDS PHYSICS 20 GRAVITATIONAL FORCES. Gravitational Fields (or Acceleration Due to Gravity) Symbol: Definition: Units:

GRAVITATIONAL FIELDS Gravitational Fields (or Acceleration Due to Gravity) Symbol: Definition: Units: Formula Description This is the formula for force due to gravity or as we call it, weight. Relevant

### Name Class Period. F = G m 1 m 2 d 2. G =6.67 x 10-11 Nm 2 /kg 2

Gravitational Forces 13.1 Newton s Law of Universal Gravity Newton discovered that gravity is universal. Everything pulls on everything else in the universe in a way that involves only mass and distance.

### Astronomy 1140 Quiz 1 Review

Astronomy 1140 Quiz 1 Review Prof. Pradhan September 15, 2015 What is Science? 1. Explain the difference between astronomy and astrology. (a) Astrology: nonscience using zodiac sign to predict the future/personality

### How To Understand The Theory Of Gravity

Newton s Law of Gravity and Kepler s Laws Michael Fowler Phys 142E Lec 9 2/6/09. These notes are partly adapted from my Physics 152 lectures, where more mathematical details can be found. The Universal

### Unit 8 Lesson 2 Gravity and the Solar System

Unit 8 Lesson 2 Gravity and the Solar System Gravity What is gravity? Gravity is a force of attraction between objects that is due to their masses and the distances between them. Every object in the universe

### Name: Earth 110 Exploration of the Solar System Assignment 1: Celestial Motions and Forces Due in class Tuesday, Jan. 20, 2015

Name: Earth 110 Exploration of the Solar System Assignment 1: Celestial Motions and Forces Due in class Tuesday, Jan. 20, 2015 Why are celestial motions and forces important? They explain the world around

### The University of Texas at Austin. Gravity and Orbits

UTeach Outreach The University of Texas at Austin Gravity and Orbits Time of Lesson: 60-75 minutes Content Standards Addressed in Lesson: TEKS6.11B understand that gravity is the force that governs the

### Satellites and Space Stations

Satellites and Space Stations A satellite is an object or a body that revolves around another object, which is usually much larger in mass. Natural satellites include the planets, which revolve around

### The Hidden Lives of Galaxies. Jim Lochner, USRA & NASA/GSFC

The Hidden Lives of Galaxies Jim Lochner, USRA & NASA/GSFC What is a Galaxy? Solar System Distance from Earth to Sun = 93,000,000 miles = 8 light-minutes Size of Solar System = 5.5 light-hours What is

### 2. Orbits. FER-Zagreb, Satellite communication systems 2011/12

2. Orbits Topics Orbit types Kepler and Newton laws Coverage area Influence of Earth 1 Orbit types According to inclination angle Equatorial Polar Inclinational orbit According to shape Circular orbit

### Chapter 5: Circular Motion, the Planets, and Gravity

Chapter 5: Circular Motion, the Planets, and Gravity 1. Earth s gravity attracts a person with a force of 120 lbs. The force with which the Earth is attracted towards the person is A. Zero. B. Small but

### Background Information

Background Information The Second Law of Motion and The Law of Gravitation Student Activities 1. Round and Round They Go! 2. onic Sections - Movement in Newton s Gravitational orce Notes to Teachers Teacher

### 4 Gravity: A Force of Attraction

CHAPTER 1 SECTION Matter in Motion 4 Gravity: A Force of Attraction BEFORE YOU READ After you read this section, you should be able to answer these questions: What is gravity? How are weight and mass different?

### Use the following information to deduce that the gravitational field strength at the surface of the Earth is approximately 10 N kg 1.

IB PHYSICS: Gravitational Forces Review 1. This question is about gravitation and ocean tides. (b) State Newton s law of universal gravitation. Use the following information to deduce that the gravitational

### Newton s Law of Universal Gravitation

12.1 Newton s Law of Universal Gravitation SECTION Explain Kepler s laws. Describe Newton s law of universal gravitation. Apply Newton s law of universal gravitation quantitatively. KEY TERMS OUTCOMES

### Planetary Orbit Simulator Student Guide

Name: Planetary Orbit Simulator Student Guide Background Material Answer the following questions after reviewing the Kepler's Laws and Planetary Motion and Newton and Planetary Motion background pages.

### Orbital Mechanics. Angular Momentum

Orbital Mechanics The objects that orbit earth have only a few forces acting on them, the largest being the gravitational pull from the earth. The trajectories that satellites or rockets follow are largely

### Solar System. 1. The diagram below represents a simple geocentric model. Which object is represented by the letter X?

Solar System 1. The diagram below represents a simple geocentric model. Which object is represented by the letter X? A) Earth B) Sun C) Moon D) Polaris 2. Which object orbits Earth in both the Earth-centered

### Exercise: Estimating the Mass of Jupiter Difficulty: Medium

Exercise: Estimating the Mass of Jupiter Difficulty: Medium OBJECTIVE The July / August observing notes for 010 state that Jupiter rises at dusk. The great planet is now starting its grand showing for

### Niraj Sir GRAVITATION CONCEPTS. Kepler's law of planetry motion

GRAVITATION CONCEPTS Kepler's law of planetry motion (a) Kepler's first law (law of orbit): Every planet revolves around the sun in an elliptical orbit with the sun is situated at one focus of the ellipse.

### GRAVITY CONCEPTS. Gravity is the universal force of attraction between all matter

IT S UNIVERSAL GRAVITY CONCEPTS Gravity is the universal force of attraction between all matter Weight is a measure of the gravitational force pulling objects toward Earth Objects seem weightless when

### ELEMENTS OF PHYSICS MOTION, FORCE, AND GRAVITY

1 Pre-Test Directions: This will help you discover what you know about the subject of motion before you begin this lesson. Answer the following true or false. 1. Aristotle believed that all objects fell

### A. 81 2 = 6561 times greater. B. 81 times greater. C. equally strong. D. 1/81 as great. E. (1/81) 2 = 1/6561 as great.

Q12.1 The mass of the Moon is 1/81 of the mass of the Earth. Compared to the gravitational force that the Earth exerts on the Moon, the gravitational force that the Moon exerts on the Earth is A. 81 2

### Chapter 25.1: Models of our Solar System

Chapter 25.1: Models of our Solar System Objectives: Compare & Contrast geocentric and heliocentric models of the solar sytem. Describe the orbits of planets explain how gravity and inertia keep the planets

### Educator Guide to S LAR SYSTEM. 1875 El Prado, San Diego CA 92101 (619) 238-1233 www.rhfleet.org

Educator Guide to S LAR SYSTEM 1875 El Prado, San Diego CA 92101 (619) 238-1233 www.rhfleet.org Pre-Visit Activity: Orbital Paths Materials: Plastic Plate Marble Scissors To Do: 1. Put the plate on a flat

### Study Guide: Solar System

Study Guide: Solar System 1. How many planets are there in the solar system? 2. What is the correct order of all the planets in the solar system? 3. Where can a comet be located in the solar system? 4.

### Physics 2A, Sec B00: Mechanics -- Winter 2011 Instructor: B. Grinstein Final Exam

Physics 2A, Sec B00: Mechanics -- Winter 2011 Instructor: B. Grinstein Final Exam INSTRUCTIONS: Use a pencil #2 to fill your scantron. Write your code number and bubble it in under "EXAM NUMBER;" an entry

### Forces. When an object is pushed or pulled, we say that a force is exerted on it.

Forces When an object is pushed or pulled, we say that a force is exerted on it. Forces can Cause an object to start moving Change the speed of a moving object Cause a moving object to stop moving Change

### Why don t planets crash into each other?

1 Just as we know that the sun will rise every morning, we expect the planets and the moon to stay in their orbits. And rightly so. For 400 years, people have understood that the movements of Earth, the

### The Gravitational Field

The Gravitational Field The use of multimedia in teaching physics Texts to multimedia presentation Jan Hrnčíř jan.hrncir@gfxs.cz Martin Klejch martin.klejch@gfxs.cz F. X. Šalda Grammar School, Liberec

### Gravity. in the Solar System. Beyond the Book. FOCUS Book

FOCUS Book Design a test to find out whether Earth s gravity always pulls straight down. A pendulum is a weight that hangs from a string or rod that can swing back and forth. Use string and metal washers

### DIRECT ORBITAL DYNAMICS: USING INDEPENDENT ORBITAL TERMS TO TREAT BODIES AS ORBITING EACH OTHER DIRECTLY WHILE IN MOTION

1 DIRECT ORBITAL DYNAMICS: USING INDEPENDENT ORBITAL TERMS TO TREAT BODIES AS ORBITING EACH OTHER DIRECTLY WHILE IN MOTION Daniel S. Orton email: dsorton1@gmail.com Abstract: There are many longstanding

### Solar System Fundamentals. What is a Planet? Planetary orbits Planetary temperatures Planetary Atmospheres Origin of the Solar System

Solar System Fundamentals What is a Planet? Planetary orbits Planetary temperatures Planetary Atmospheres Origin of the Solar System Properties of Planets What is a planet? Defined finally in August 2006!

### What Do You Think? For You To Do GOALS

Activity 2 Newton s Law of Universal Gravitation GOALS In this activity you will: Explore the relationship between distance of a light source and intensity of light. Graph and analyze the relationship

### Lab 6: Kepler's Laws. Introduction. Section 1: First Law

Lab 6: Kepler's Laws Purpose: to learn that orbit shapes are ellipses, gravity and orbital velocity are related, and force of gravity and orbital period are related. Materials: 2 thumbtacks, 1 pencil,

### 5. Forces and Motion-I. Force is an interaction that causes the acceleration of a body. A vector quantity.

5. Forces and Motion-I 1 Force is an interaction that causes the acceleration of a body. A vector quantity. Newton's First Law: Consider a body on which no net force acts. If the body is at rest, it will

### Newton s Laws. Newton s Imaginary Cannon. Michael Fowler Physics 142E Lec 6 Jan 22, 2009

Newton s Laws Michael Fowler Physics 142E Lec 6 Jan 22, 2009 Newton s Imaginary Cannon Newton was familiar with Galileo s analysis of projectile motion, and decided to take it one step further. He imagined

### PHYS 117- Exam I. Multiple Choice Identify the letter of the choice that best completes the statement or answers the question.

PHYS 117- Exam I Multiple Choice Identify the letter of the choice that best completes the statement or answers the question. 1. Car A travels from milepost 343 to milepost 349 in 5 minutes. Car B travels

### Newton s Laws of Motion

Newton s Laws of Motion The Earth revolves around the sun in an elliptical orbit. The moon orbits the Earth in the same way. But what keeps the Earth and the moon in orbit? Why don t they just fly off

### The Solar System. Unit 4 covers the following framework standards: ES 10 and PS 11. Content was adapted the following:

Unit 4 The Solar System Chapter 7 ~ The History of the Solar System o Section 1 ~ The Formation of the Solar System o Section 2 ~ Observing the Solar System Chapter 8 ~ The Parts the Solar System o Section

### astronomy 2008 1. A planet was viewed from Earth for several hours. The diagrams below represent the appearance of the planet at four different times.

1. A planet was viewed from Earth for several hours. The diagrams below represent the appearance of the planet at four different times. 5. If the distance between the Earth and the Sun were increased,

### How To Understand General Relativity

Chapter S3 Spacetime and Gravity What are the major ideas of special relativity? Spacetime Special relativity showed that space and time are not absolute Instead they are inextricably linked in a four-dimensional

RETURN TO THE MOON Lesson Plan INSTRUCTIONS FOR TEACHERS Grade Level: 9-12 Curriculum Links: Earth and Space (SNC 1D: D2.1, D2.2, D2.3, D2.4) Group Size: Groups of 2-4 students Preparation time: 1 hour

### AE554 Applied Orbital Mechanics. Hafta 1 Egemen Đmre

AE554 Applied Orbital Mechanics Hafta 1 Egemen Đmre A bit of history the beginning Astronomy: Science of heavens. (Ancient Greeks). Astronomy existed several thousand years BC Perfect universe (like circles

### Grade 6 Standard 3 Unit Test A Astronomy. 1. The four inner planets are rocky and small. Which description best fits the next four outer planets?

Grade 6 Standard 3 Unit Test A Astronomy Multiple Choice 1. The four inner planets are rocky and small. Which description best fits the next four outer planets? A. They are also rocky and small. B. They

### Newton s Law of Gravitation

Newton s Law of Gravitation Duration: 1-2 class periods Essential Questions: How do the acceleration and force due to gravity depend on the radius and mass of a planet? How does the mass of a falling body

### Chapter 3.8 & 6 Solutions

Chapter 3.8 & 6 Solutions P3.37. Prepare: We are asked to find period, speed and acceleration. Period and frequency are inverses according to Equation 3.26. To find speed we need to know the distance traveled

### Chapter 3 The Science of Astronomy

Chapter 3 The Science of Astronomy Days of the week were named for Sun, Moon, and visible planets. What did ancient civilizations achieve in astronomy? Daily timekeeping Tracking the seasons and calendar

### EDMONDS COMMUNITY COLLEGE ASTRONOMY 100 Winter Quarter 2007 Sample Test # 1

Instructor: L. M. Khandro EDMONDS COMMUNITY COLLEGE ASTRONOMY 100 Winter Quarter 2007 Sample Test # 1 1. An arc second is a measure of a. time interval between oscillations of a standard clock b. time

### Forces between masses

Forces between masses Gravity is arguably the first force that people really learn about. People don't really think of it as learning about gravity because it is such a big part of our everyday lives.

### Version A Page 1. 1. The diagram shows two bowling balls, A and B, each having a mass of 7.00 kilograms, placed 2.00 meters apart.

Physics Unit Exam, Kinematics 1. The diagram shows two bowling balls, A and B, each having a mass of 7.00 kilograms, placed 2.00 meters apart. What is the magnitude of the gravitational force exerted by

### Physics 53. Gravity. Nature and Nature's law lay hid in night: God said, "Let Newton be!" and all was light. Alexander Pope

Physics 53 Gravity Nature and Nature's law lay hid in night: God said, "Let Newton be!" and all was light. Alexander Pope Kepler s laws Explanations of the motion of the celestial bodies sun, moon, planets

### Lesson 29: Newton's Law of Universal Gravitation

Lesson 29: Newton's Law of Universal Gravitation Let's say we start with the classic apple on the head version of Newton's work. Newton started with the idea that since the Earth is pulling on the apple,

### The orbit of Halley s Comet

The orbit of Halley s Comet Given this information Orbital period = 76 yrs Aphelion distance = 35.3 AU Observed comet in 1682 and predicted return 1758 Questions: How close does HC approach the Sun? What

### Section 4: The Basics of Satellite Orbits

Section 4: The Basics of Satellite Orbits MOTION IN SPACE VS. MOTION IN THE ATMOSPHERE The motion of objects in the atmosphere differs in three important ways from the motion of objects in space. First,

### Sample Questions for the AP Physics 1 Exam

Sample Questions for the AP Physics 1 Exam Sample Questions for the AP Physics 1 Exam Multiple-choice Questions Note: To simplify calculations, you may use g 5 10 m/s 2 in all problems. Directions: Each

### Newton s Law of Gravity

Gravitational Potential Energy On Earth, depends on: object s mass (m) strength of gravity (g) distance object could potentially fall Gravitational Potential Energy In space, an object or gas cloud has

### The Solar System. Source http://starchild.gsfc.nasa.gov/docs/starchild/solar_system_level1/solar_system.html

The Solar System What is the solar system? It is our Sun and everything that travels around it. Our solar system is elliptical in shape. That means it is shaped like an egg. Earth s orbit is nearly circular.

### UNIT V. Earth and Space. Earth and the Solar System

UNIT V Earth and Space Chapter 9 Earth and the Solar System EARTH AND OTHER PLANETS A solar system contains planets, moons, and other objects that orbit around a star or the star system. The solar system

### Physics 111: Lecture 4: Chapter 4 - Forces and Newton s Laws of Motion. Physics is about forces and how the world around us reacts to these forces.

Physics 111: Lecture 4: Chapter 4 - Forces and Newton s Laws of Motion Physics is about forces and how the world around us reacts to these forces. Whats a force? Contact and non-contact forces. Whats a

### Chapter 4: Newton s Laws: Explaining Motion

Chapter 4: Newton s Laws: Explaining Motion 1. All except one of the following require the application of a net force. Which one is the exception? A. to change an object from a state of rest to a state

### PHY121 #8 Midterm I 3.06.2013

PHY11 #8 Midterm I 3.06.013 AP Physics- Newton s Laws AP Exam Multiple Choice Questions #1 #4 1. When the frictionless system shown above is accelerated by an applied force of magnitude F, the tension

### Carol and Charles see their pencils fall exactly straight down.

Section 24-1 1. Carol is in a railroad car on a train moving west along a straight stretch of track at a constant speed of 120 km/h, and Charles is in a railroad car on a train at rest on a siding along

### Astronomy 110 Homework #04 Assigned: 02/06/2007 Due: 02/13/2007. Name:

Astronomy 110 Homework #04 Assigned: 02/06/2007 Due: 02/13/2007 Name: Directions: Listed below are twenty (20) multiple-choice questions based on the material covered by the lectures this past week. Choose

### Supplemental Questions

Supplemental Questions The fastest of all fishes is the sailfish. If a sailfish accelerates at a rate of 14 (km/hr)/sec [fwd] for 4.7 s from its initial velocity of 42 km/h [fwd], what is its final velocity?

### Conceptual Questions: Forces and Newton s Laws

Conceptual Questions: Forces and Newton s Laws 1. An object can have motion only if a net force acts on it. his statement is a. true b. false 2. And the reason for this (refer to previous question) is

### Physics 9e/Cutnell. correlated to the. College Board AP Physics 1 Course Objectives

Physics 9e/Cutnell correlated to the College Board AP Physics 1 Course Objectives Big Idea 1: Objects and systems have properties such as mass and charge. Systems may have internal structure. Enduring

### Physics Midterm Review Packet January 2010

Physics Midterm Review Packet January 2010 This Packet is a Study Guide, not a replacement for studying from your notes, tests, quizzes, and textbook. Midterm Date: Thursday, January 28 th 8:15-10:15 Room:

### Chapter 10 Rotational Motion. Copyright 2009 Pearson Education, Inc.

Chapter 10 Rotational Motion Angular Quantities Units of Chapter 10 Vector Nature of Angular Quantities Constant Angular Acceleration Torque Rotational Dynamics; Torque and Rotational Inertia Solving Problems

### Conceptual: 1, 3, 5, 6, 8, 16, 18, 19. Problems: 4, 6, 8, 11, 16, 20, 23, 27, 34, 41, 45, 56, 60, 65. Conceptual Questions

Conceptual: 1, 3, 5, 6, 8, 16, 18, 19 Problems: 4, 6, 8, 11, 16, 20, 23, 27, 34, 41, 45, 56, 60, 65 Conceptual Questions 1. The magnetic field cannot be described as the magnetic force per unit charge

### Physics: Principles and Applications, 6e Giancoli Chapter 4 Dynamics: Newton's Laws of Motion

Physics: Principles and Applications, 6e Giancoli Chapter 4 Dynamics: Newton's Laws of Motion Conceptual Questions 1) Which of Newton's laws best explains why motorists should buckle-up? A) the first law

### Introduction to the Solar System

Introduction to the Solar System Lesson Objectives Describe some early ideas about our solar system. Name the planets, and describe their motion around the Sun. Explain how the solar system formed. Introduction

### Q3.2.a The gravitational force exerted by a planet on one of its moons is 3e23 newtons when the moon is at a particular location.

Q3.2.a The gravitational force exerted by a planet on one of its moons is 3e23 newtons when the moon is at a particular location. If the mass of the moon were three times as large, what would the force

### Study Guide due Friday, 1/29

NAME: Astronomy Study Guide asteroid chromosphere comet corona ellipse Galilean moons VOCABULARY WORDS TO KNOW geocentric system meteor gravity meteorite greenhouse effect meteoroid heliocentric system

### Newton s Laws. Physics 1425 lecture 6. Michael Fowler, UVa.

Newton s Laws Physics 1425 lecture 6 Michael Fowler, UVa. Newton Extended Galileo s Picture of Galileo said: Motion to Include Forces Natural horizontal motion is at constant velocity unless a force acts:

### III. Applications of Force and Motion Concepts. Concept Review. Conflicting Contentions. 1. Airplane Drop 2. Moving Ball Toss 3. Galileo s Argument

III. Applications of Force and Motion Concepts Concept Review Conflicting Contentions 1. Airplane Drop 2. Moving Ball Toss 3. Galileo s Argument Qualitative Reasoning 1. Dropping Balls 2. Spinning Bug

### 1. Mass, Force and Gravity

STE Physics Intro Name 1. Mass, Force and Gravity Before attempting to understand force, we need to look at mass and acceleration. a) What does mass measure? The quantity of matter(atoms) b) What is the

### Physics 11 Assignment KEY Dynamics Chapters 4 & 5

Physics Assignment KEY Dynamics Chapters 4 & 5 ote: for all dynamics problem-solving questions, draw appropriate free body diagrams and use the aforementioned problem-solving method.. Define the following

### AP1 Oscillations. 1. Which of the following statements about a spring-block oscillator in simple harmonic motion about its equilibrium point is false?

1. Which of the following statements about a spring-block oscillator in simple harmonic motion about its equilibrium point is false? (A) The displacement is directly related to the acceleration. (B) The

### Penn State University Physics 211 ORBITAL MECHANICS 1

ORBITAL MECHANICS 1 PURPOSE The purpose of this laboratory project is to calculate, verify and then simulate various satellite orbit scenarios for an artificial satellite orbiting the earth. First, there

### A Determination of g, the Acceleration Due to Gravity, from Newton's Laws of Motion

A Determination of g, the Acceleration Due to Gravity, from Newton's Laws of Motion Objective In the experiment you will determine the cart acceleration, a, and the friction force, f, experimentally for

### NASA Explorer Schools Pre-Algebra Unit Lesson 2 Student Workbook. Solar System Math. Comparing Mass, Gravity, Composition, & Density

National Aeronautics and Space Administration NASA Explorer Schools Pre-Algebra Unit Lesson 2 Student Workbook Solar System Math Comparing Mass, Gravity, Composition, & Density What interval of values

### CHAPTER 6 WORK AND ENERGY

CHAPTER 6 WORK AND ENERGY CONCEPTUAL QUESTIONS. REASONING AND SOLUTION The work done by F in moving the box through a displacement s is W = ( F cos 0 ) s= Fs. The work done by F is W = ( F cos θ). s From

### Newton s Law of Universal Gravitation describes the attractive gravitational force that exists between any two bodies with the following equation:

Newton s Laws & Gravitation Newton s Law of Universal Gravitation describes the attractive gravitational force that exists between any two bodies with the following equation: F G = GMm 2 r G is the gravitational

### Inertia, Forces, and Acceleration: The Legacy of Sir Isaac Newton

Inertia, Forces, and Acceleration: The Legacy of Sir Isaac Newton Position is a Vector Compare A A ball is 12 meters North of the Sun God to A A ball is 10 meters from here A vector has both a direction

### Review Chapters 2, 3, 4, 5

Review Chapters 2, 3, 4, 5 4) The gain in speed each second for a freely-falling object is about A) 0. B) 5 m/s. C) 10 m/s. D) 20 m/s. E) depends on the initial speed 9) Whirl a rock at the end of a string

### Related Standards and Background Information

Related Standards and Background Information Earth Patterns, Cycles and Changes This strand focuses on student understanding of patterns in nature, natural cycles, and changes that occur both quickly and