Energy and Energy Transformations Test Review Completion: 1. Mass 13. Kinetic 2. Four 14. thermal 3. Kinetic 15. Thermal energy (heat) 4. Electromagnetic/Radiant 16. Thermal energy (heat) 5. Thermal 17. conduction 6. Kinetic 18. radiation 7. Mechanical 19. insulator 8. Conservation of energy 20. conductor 9. Chemical 21. heat 10. Energy 22. Expand (get bigger) 11. Electrical 23. Expand (get bigger) 12. Potential 24. Decreases (goes down) Short Answer: 25. C. At this point, which is the highest point, all of the ball s energy is gravitational potential energy. The ball does not have kinetic energy because it is not moving at this point. 26. E. As the ball falls from C to E, potential energy is converted to kinetic energy. The velocity of the ball increases as it falls, which means that the ball attains its greatest velocity, and this its greatest kinetic energy at E. 27. E. The potential energy of the ball depends on its height. Since E is the lowest point, the ball has the least amount of potential energy at this point. 28. C. Kinetic energy depends on the speed of the ball. As the basll rises from A to C, it slows down until the point at which it changes direction and begins to fall. 29. It is used to let light in but prevent heat loss. 30. Heat (thermal energy) transfer by conduction. 31. The air space is a good insulator, which reduces heat transfer. 32. Air is poor conductor of heat and thus acts as an insulator. The air space reduced the heat transfers by conduction. 33. The metallic coating limits heat transfer by radiation, because the shiny surface reflects electromagnetic waves or radiant energy. 34. Without an air layer, the single pane allows heat to escape easily by conduction.
1. Describe the three types of heat transfer (Remember that describe means to tell everything you know and give examples). Convection-- Heat transfer through fluids Ex: Convection currents in the mantle, steam coming off of a cup of hot chocolate, water heating in a pot, etc. Conduction heat transfer through touching Ex: Cup of hot chocolate warming your hands as you hold it, electric burner heating the pot, hot fluid heating a spoon that stirs it, etc. Radiation heat transfer through space Ex: Sun s rays heating a pool of water, warming your hands by a fire, the heat your hands feel when you put them next to something to see if it s hot, etc. 2. What is energy? Energy is the ability to do work or cause change 3. Identify the two main forms of energy. Potential and Kinetic 4. Draw a picture of a person tossing a baseball in the air and catching it. (You can use stick figures) Explain how energy moves between potential and kinetic from the point the person is holding the ball, tosses it into the air and then catches it. Label the spot(s) where potential energy is the greatest and the spot(s) where the kinetic energy is the greatest. When the person is holding the ball in his hand, the ball is at rest and has 100% potential energy. When he tosses it in the air, the energy transforms from potential to kinetic. The ball has the greatest potential energy when it is at the top of the arc in the air and it begins to fall. It is highest there due to the added height over holding it in his hand. The ball has the greatest kinetic energy at the point it leaves his hand and the point right before it hits his hand to catch it. 5. Describe the following types of energy: Mechanical, thermal, chemical, electrical, electromagnetic, and nuclear. Mechanical Energy The total amount of potential and kinetic energy in a system or the movement of machine parts. Ex: Wind turbine turning in the wind, all of the potential and kinetic energy combined when the person is tossing the ball and catching it. Thermal Energy Total energy of the particles that make up a substance or object caused by the vibration and movement of atoms and molecules. Ex: boiling water, school table. All objects have thermal energy unless it is at absolute zero. The larger the amount of something, the more thermal energy it will have because it has more atoms and molecules. Remember iceberg vs boiling pan of water. The iceberg has more thermal energy because it is larger and has more molecules than the boiling water. Remember that heat is the transfer of thermal energy.
Chemical Potential energy stored in the bonds of atoms and molecules Ex: batteries, fossil fuels, energy created by plants as they go through photosynthesis Electrical Energy electrical charges carry Ex: Lightning, blow dryer, fan Electromagnetic (Radiant) kinetic energy that travels in the form of waves. Does not need a medium in which to travel Ex: Light from the sun, microwaves, x-rays Nuclear Energy Potential energy stored in the nucleus of the atom Ex: Fission and fusion 6. Explain what is meant by thermal equilibrium. Thermal equilibrium is met when all parts of the system are the same temperature (Think about all items in the room being room temperature even if they don t feel that way. Remember the lab with the 3 temperatures of water.) 7. Explain the difference between energy transfer and an energy transformation. Energy transfer is moving energy from one place to another. It will continue to be the same type of energy. An energy transformation is when energy moves from one type (form) to another as energy travels through the objects. 8. Explain the law of conservation of energy. The law of conservation of energy states that energy cannot be created or destroyed, it can only change from one form to another. This means that as energy moves throughout a system, the amount of energy you start with is the amount of energy you end with. 9. List and describe 5 different examples of energy transformations. Glow stick The glow stick has chemical potential energy that is transformed into radiant energy when the chemicals are combined when the stick is broken. Wind up Car When you push down on the car (or pull back on the car) you transfer kinetic energy by compressing the spring. The car now has stored mechanical energy (or elastic potential energy). When you release the car that potential energy is transformed into kinetic energy. Radiometer As the black vanes absorb radiant energy from the lamp, that radiant energy is transformed into thermal energy which causes motion. Battery- Chemical energy from the apple was converted into electrical energy. Radio- Electrical energy changes to sound energy when it s turned on. 11. Explain the motion (behavior) of atoms and molecules as they are heated or cooled. How is this related to kinetic energy?
When atoms and molecules are heated, they begin to move more rapidly. When atoms and molecules are cooled, their movement slows down. Kinetic energy is the measurement of movement. Since these particles move more when they are heated, they have more kinetic energy. The particles move less when they are cooled and have less kinetic energy. 12. Explain how density of materials changes as they are heated or cooled. As material is heated, it becomes less dense because the atoms are moving more quickly. As materials are cooled, they become more dense as atoms slow down. 13. What is a conductor? Give some examples of materials that are good conductors. A good conductor would transfer energy (heat, electricity) easily from one place to another. It is usually dense material. Some conductors are: metal (aluminum, steel, copper, etc.) electrical wire, ceramic, glass, etc. 14. What is an insulator? Give some examples of materials that are good insulators. A good insulator would keep energy (heat, electricity) from transferring from one place to another. Some insulators could be: Styrofoam, thick plastic, cloth, wood, etc 15. Define a wave. A disturbance that transfers energy from one place to another 16. Describe longitudinal/compressional waves (words along with diagrams will be helpful here). Longitudinal/Compression----waves that push together and pull apart (compress and release). These waves move the particles of the medium parallel to the direction in which the wave moves. Think of the wave moving through the slinky. 17. Draw a transverse wave in the space below. In the drawing include the following: amplitude, wavelength, crest, trough, and rest position.
Equilibrium position is the same as resting position. 18. What are the steps of the scientific method? Identify a problem write a question you want to investigate Form a hypothesis Predict the answer to the question Create an experiment Develop a procedure for a reliable experiment Perform the experiment Record your data and observations Analyze the Data do the data and observations support your hypothesis Share the results write a conclusion 19. What is the difference between Quantitative Data and Qualitative Data? Qualitative data is described in words. Uses the five senses, includes things like smell, texture, color, shape, etc. Quantitative data is described in numbers. Usually can be graphed. Examples include length, mass, time, number, temperature. 20. What is the correct way of writing a hypothesis? Give an example of a well-written hypothesis. Hypothesis are always written in an if, then format. If I change the number of hours a plant is in the sun, then the plant with the most hours of sunlight will grow the most.