Answer the following questions by marking the BEST answer choice on the answer sheet

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1 Answer the following questions by marking the BEST answer choice on the answer sheet 1. What is the average speed of a car that travels a total distance of 320 meters in 2.6 minutes? a. 2.1 m/s b. 120 m/s c m/s d m/s 2. An object of mass M is separated from an object of mass 2M by a distance of 2d. I a third mass of m is placed at the halfway point between the first and second masses, what will the magnitude of the net force on the object of mass m? a. GMm/2d² b. GMm/d² c. 2GMm/d² d. 2GMm/2d² 3. A single slit diffraction pattern is obtained on a screen using yellow light. If the yellow light is replaced by blue light without making any other changes in the experimental set up, what will happen to the diffraction bands? a. Bands will become narrower and crowded together b. Bands will disappear c. Bands will become narrower and farther apart d. Bands will become broader and crowded together 4. A shuttle is launched from the surface of a planet with mass M and radius R. What is the minimum velocity the shuttle must be given to completely escape from the planet s gravitational field? a. V = (GM/R) b. V = (GM/R²) c. V = (2GM/R²) d. V = (2GM/R) 5. A loop of wire enclosing an area of 1.5 m² is placed perpendicular to a magnetic field. The field is given in teslas as a function of time t in seconds by: B(t) = (20t/3) 10 The induced emf in the loop at t = 6 sec is most nearly: a. 20 V b. 30 V c. 40 V d. 50 V 6. A small cylinder rolling with a velocity v along a horizontal surface encounters a smooth inclined surface. The height h up to which the cylinder will ascend is a. 3v 2 /2g b. 3v 2 /4g c. v 2 /2g d. v 2 /4g

2 7. The velocity of a particle moving along the x-axis varies in time according to the expression v(x) = (40 5t²) m/s, where t is in seconds. Find the average acceleration in the time interval t = 0 to t = 2.0 s. a. 10 m/s² b. 10 m/s² c m/s² d m/s² 8. Three particles lie on the coordinate plane: mass m, at point (1, 3); mass 2m, at point (-1, 2), and mass 3m, at point (4, -2). Where is the center of mass of the three-particle system? a. ( 11,1) b. (11/3, 2/3) c. (11/6, 1/6) d. (1/6, 1/6) 9. A bar magnet is thrust into a coil of wire as indicated in the diagram. Which of the following statements concerning this experiment is correct? a. The polarity of the coil at H is South, at G is North, and the induced current is indicated by arrow Y. b. The polarity of the coil at H is North, at G is South, and the induced current is indicated by arrow X. c. The polarity of the coil at H is South, at G is North, and the induced current is indicated by arrow X. d. The polarity of the coil at H is North, at G is South, and the induced current is indicated by arrow Y. 10. Newton s first law of motion, also called the law of inertia, states that: a. If an object does not interact with other objects, it is possible to identify a reference frame in which the object has zero acceleration.

3 b. The acceleration of an object is directly proportional to the net force acting on it and inversely proportional to its mass. c. If two objects interact, the force exerted by one object onto another is equal in magnitude and opposite in direction d. None of these 11. In what direction will the net force be for a 10-N ball that is moving horizontally and experiencing an air drag of 10 N? a N at 45 below the horizontal b. 10 N at 45 below the horizontal c N at 45 above the horizontal d. 10 N at 45 above the horizontal 12. If a 2 ft. by 2 ft. block has two applied forces of 5N and 10N moving horizontal in the positive x direction, what would be the net force? a. 5N b. 10N c. 15N d. -5N 13. Solve for a (acceleration) in the net force equation. a. a = F + m b. a = Fm c. a = F/m d. a = m/f 14. In a mass spectrograph, positive ions moving with different velocities in the positive X-direction are admitted into a velocity filter in which an electric field of magnitude E is applied in the negative Y- direction. What should be the direction of the magnetic field so that ions of the same velocity pass through the velocity filter without deflection? a. Positive Z-direction b. Negative Y-direction c. Positive X-direction d. Negative Z-direction 15. The longest wavelength photon in the visible Balmer series for the hydrogen atom is: a nm b nm c. 656 nm d nm 16. A wheel starts from rest and rotates through 1000 radians in 10 s under the action of a constant torque. If the moment of inertia of the wheel is 4 kg m 2, the torque acting on the wheel is what? a. 10Nm b. 20Nm c. 40Nm d. 80Nm

4 17. An iceberg floating in sea water just sinks when a mass of 360 kg is placed on it. What is the mass of the iceberg? (Relative density of sea water = 1.02; relative density of ice = 0.9) a. 2700kg b. 2400kg c. 1800kg d. 1500kg 18. Which one of these equations represents Bernoulli s theorem? a. P + ρgh + (½)ρv 2 = constant b. R= 2 *h(h h)] c. A 1 v 1 = A 2 v 2 d. h = v 2 /2g 19. A free rectangular current carrying loop ABCD is shown, near a long straight conductor PQ carrying a current I. The plane of the loop is the same as the plane containing the straight conductor and two sides of the loop are parallel to the straight conductor. The loop will then: a. move away from the straight conductor b. move towards the straight conductor c. rotate clockwise d. rotate anticlockwise 20. In Young s double slit experiment, there are 8 bands of double slit interference patterns with the separation between each slit being 1 mm. Therefore, the width of each slit is: a. 0.2mm b. 0.25mm c. 0.4mm d. 0.5mm 21. Which of these equations is the correct formula for torque? a. τ = I α b. P = τω c. L = Iω d. dw = τ dθ 22. Two point charges Q 1 and Q 2, respectively, are separated by.3 meters. If the Coulomb force between them is.21 N and Q 1 = 1.7 times Q 2, what is Q 2 to the nearest hundredth of a microc?

5 a b c d Rewrite the number in scientific notation. a X 10 ⁴ b X 10⁴ c X 10 ⁵ d X 10⁵ 24. The new rollercoaster called the Python consists of a 125 kg cart in which two people can ride. The cart, which is initially at rest, rolls down an incline that is 20 meters long at an angle of 10 o to the horizontal. The height of the first hill is 15 meters. Calculate the velocity of the cart when it reaches the bottom of the first hill. a m/s b m/s c m/s d m/s 25. An organ pipe which is open at both ends resonates with a fundamental frequency of 500 Hz. If one end of the pipe is closed, it will resonate with a fundamental frequency of: a. 100 Hz b. 175 Hz c. 250 Hz d. 500 Hz 26. What is the current in the 2Ω resistor while the switch S is open (the battery has zero internal resistance)? a. 0 A b. 6 A c. 1.2 A d A 27. The wavelength of yellow sodium light in vacuum is 5.89 X 10 ⁷ m. The speed of this light in glass with an index of refraction of 1.5 is most nearly: a. 9 X 10 ⁷ m/s b. 4 X 10⁸ m/s c. 3 X 10 ⁷ m/s d. 2 X 10⁸ m/s 28. A glowing ember(hot piece of charcoal) radiates power P in watts at an absolute temperature T. When the temperature of the ember has decreased to T/2, the power it radiates is: a. P/2 b. P/8 c. P/16 d. P/4

6 29. A block of ice with mass m falls into the Atlantic Ocean. After impact, a mass of ice m/5 melts. Both the block of ice and the Atlantic Ocean have a temperature of 0 C. If L represents the heat of fusion, the minimum distance the ice fell is: a. 5L/g b. L/5g c. 5gL/m d. gl/5m 30. A woman went out for a walk with her dog. She left her home and started walking at a constant velocity. After a period of time they stopped in the park to take a short break and then continued walking with a greater velocity then they originally started out with. Then it started getting dark so they turned around and quickly walked back home. Which of the following graphs best represents the distance versus time graph for the woman s walk? a. b. c. d. 31. In a rescue attempt, a hovering helicopter drops a life preserver to a swimmer being swept downstream by a river current of constant velocity v. The helicopter is at a height of 9.8m. If the swimmer id 6.0m upstream from a point directly under the helicopter when the life preserver is released and it lands 2.0m in front of the swimmer, how fast is the current flowing? (Neglect air resistance.) a. 2.8 m/s b. 6.3 m/s c. 9.8 m/s d. 2.4 m/s 32. A pendulum is attached to the ceiling of an elevator car. When the car is parked, the pendulum exhibits a period of 1.00 s. The car now begins to travel upward with an upward acceleration of 2.3 m/s2. During this part of the motion, what will be the approximate period of the pendulum? a s b s c s d s 33. String Y and String Z have the same mass and length. String Y is under tension T and String Z is under tension 2T. The speed of waves in String Z is times the speed of waves in String Y. a b c. 1.4 d. 2.0

7 34. You are given two lenses, a converging lens with focal length +10cm and a diverging lens with focal length -20cm. Which of the following would produce a real image that is larger than an object? a. Placing the object 15cm from the converging lens. b. Placing the object1 5cm from the diverging lens. c. Placing the object 25cm from the converging lens. d. Placing the object 25cm from the diverging lens. 35. As shown in the diagram, two fixed charges, q₁ = +1.00μC and q₂ = -4.00μC, are 0.200m apart. Where is the total field zero? a. 0.40m to the left of q₁ b. 0.13m to the right of q₁ c. 0.20m to the left of q₁ d. 0.10m to the right of q₁ 36. If the heat is added at a constant volume, 6,300 joules of heat are required to raise the temperature of an ideal gas by 150 K. if instead, the heat is added at constant pressure, 8,800 joules are needed for the same temperature change. When the temperature of the gas changes by 150 K, the internal energy of the gas changes by: a. 6,300 J b. 8,800 J c. 11,300 J d. 15,100 J 37. An astronaut with weight W on Earth lands on a planet with mass 0.1 times the mass of the Earth and radius 0.5 times the radius of the Earth. The astronaut s weight is on the planet. a W b..04 W c. 0.2 W d. 0.4 W b. 38. An ideal gas is expanded at constant pressure from initial volume Vi and temperature Ti to final volume Vf and temperature Tf. The gas has molar heat capacity CP at constant pressure. The amount of work done by n moles of the gas during the process can be expressed: a. nr(tf Ti) b. nk(vf Vi) c. CPn(Tf Ti) d. nrti ln(vf/vi) 39. The average translational kinetic energy of any ideal gas depends only on: a. the absolute (Kelvin) temperature b. the mass of the gas c. the pressure of the gas

8 d. the amount of the gas 40. The system shown to the right is free to rotate about a frictionless axis through its center and perpendicular to the page. All three forces are exerted tangent to their respective rims. The magnitude of the net torque acting on the system is: a. 1.9 FR b. 1.5 FR c. 2.3 FR d. 2.5 FR END OF TEST

9 Answer Key 1. A 2. B 3. A 4. D 5. B 6. C 7. B 8. C 9. A 10. A 11. A 12. C 13. C 14. D 15. C 16. D 17. A 18. A 19. B 20. B 21. A 22. A 23. A 24. A 25. C 26. D 27. D 28. C 29. B 30. B 31. A 32. C 33. C 34. A 35. C 36. A 37. D 38. A 39. A 40. B