2012 - 2013 Study Guide
Multiple Choice
Identify the choice that best completes the statement or answers the question.
____ 1. Tides are caused by
a. / differences in the gravitational force of the sun at different points on Earth.b. / differences in the gravitational force of the moon at different points on Earth.
c. / differences in Earth’s gravitational field strength at different points on Earth’s surface.
d. / fluctuations in the gravitational attraction between Earth and the moon.
____ 2. Why does an astronaut weigh less on the moon than on Earth?
a. / The astronaut has less mass on the moon.b. / The astronaut is farther from Earth’s center when he or she is on the moon.
c. / The gravitational field strength is less on the moon’s surface than on Earth’s surface.
d. / The astronaut is continually in free fall because the moon orbits Earth.
____ 3. If you lift an apple from the ground to some point above the ground, the gravitational potential energy in the system increases. This potential energy is stored in
a. / the apple.b. / Earth.
c. / both the apple and Earth.
d. / the gravitational field between Earth and the apple.
____ 4. In this text, which of the following symbols represents gravitational field strength?
a. / F / c. / gb. / G / d. / F
____ 5. In this text, which of the following symbols represents the constant of universal gravitation?
a. / F / c. / gb. / G / d. / F
____ 6. Which of the following equations expresses Newton’s law of universal gravitation?
a. / / c. /b. / / d. /
____ 7. When calculating the gravitational force between two extended bodies, you should measure the distance
a. / from the closest points on each body.b. / from the most distant points on each body.
c. / from the center of each body.
d. / from the center of one body to the closest point on the other body.
____ 8. The gravitational force between two masses is 36 N. What is the gravitational force if the distance between them is tripled? (G = 6.673 ´ 10 N·m/kg)
a. / 4.0 N / c. / 18 Nb. / 9.0 N / d. / 27 N
____ 9. Two small masses that are 10.0 cm apart attract each other with a force of 10.0 N. When they are 5.0 cm apart, these masses will attract each other with what force?
(G = 6.673 ´ 10 N·m/kg)
a. / 5.0 N / c. / 20.0 Nb. / 2.5 N / d. / 40.0 N
____ 10. Until the middle of the 16th century, most people believed ____ was at the center of the universe.
a. / Earth / c. / the sunb. / the moon / d. / a black hole
____ 11. If you cannot exert enough force to loosen a bolt with a wrench, which of the following should you do?
a. / Use a wrench with a longer handle.b. / Tie a rope to the end of the wrench and pull on the rope.
c. / Use a wrench with a shorter handle.
d. / You should exert a force on the wrench closer to the bolt.
____ 12. A heavy bank-vault door is opened by the application of a force of 3.0 ´ 10 N directed perpendicular to the plane of the door at a distance of 0.80 m from the hinges. What is the torque?
a. / 120 N·m / c. / 300 N·mb. / 240 N·m / d. / 360 N·m
____ 13. If the torque required to loosen a nut on a wheel has a magnitude of 40.0 N·m and the force exerted by a mechanic is 133 N, how far from the nut must the mechanic apply the force?
a. / 1.20 m / c. / 30.1 cmb. / 15.0 cm / d. / 60.2 cm
____ 14. Which of the following is the equation for average velocity?
a. / / c. / v = DxDtb. / / d. /
____ 15. Which of the following units is the SI unit of velocity?
a. / meter / c. / meter per secondb. / meter·second / d. / second per meter
____ 16. In the graph above, a toy car rolls from +3 m to +5 m. Which of the following statements is true?
a. / xf = +3 m / c. / Dx = +3 mb. / xi = +3 m / d. / vavg = 3 m/s
____ 17. Suppose you are given a position versus time graph. The slope of a line drawn tangent to a point on the curve of this graph describes what quantity?
a. / acceleration / c. / instantaneous velocityb. / displacement / d. / position
____ 18. According to the graph above, the cat has the fastest speed during which interval?
a. / 0.0–5.0 s / c. / 10.0–15.0 sb. / 5.0–10.0 s / d. / 15.0–20.0 s
____ 19. Which of the following line segments on a position versus time graph is physically impossible?
a. / a horizontal line / c. / a straight line that slopes to the rightb. / a straight line that slopes to the left / d. / a vertical line
____ 20. Acceleration is defined as
a. / a rate of displacement. / c. / the change in velocity.b. / the rate of change of displacement. / d. / the rate of change of velocity.
____ 21. Which of the following is the equation for acceleration?
a. / / c. / a = DvDtb. / / d. /
____ 22. If you know the acceleration of a car, its initial velocity, and the time interval, which of the following can you predict?
a. / the direction of the car’s final velocityb. / the magnitude of the car’s final velocity
c. / the displacement of the car
d. / all of the above
____ 23. In the figure above, which diagram represents the vector addition C = A + B?
a. / I / c. / IIIb. / II / d. / IV
____ 24. In the figure above, which diagram represents the vector subtraction C = A–B?
a. / I / c. / IIIb. / II / d. / IV
____ 25. An ant on a picnic table travels 3.0 ´ 10 cm eastward, then 25 cm northward, and finally 15 cm westward. What is the magnitude of the ant’s displacement relative to its original position?
a. / 70 cm / c. / 52 cmb. / 57 cm / d. / 29 cm
____ 26. Which of the following is the motion of objects moving in two dimensions under the influence of gravity?
a. / horizontal velocity / c. / vertical velocityb. / directrix / d. / projectile motion
____ 27. Which of the following is an example of projectile motion?
a. / a jet lifting off a runwayb. / a thrown baseball
c. / an aluminum can dropped straight down into the recycling bin
d. / a space shuttle being launched
The figure above shows the path of a ball tossed from a building. Air resistance is ignored.
____ 28. At what point of the ball’s path shown in the figure above is the vertical component of the ball’s velocity zero?
a. / A / c. / Cb. / B / d. / D
____ 29. In the figure above, the horizontal component of the ball’s velocity at A is
a. / zero.b. / equal to the vertical component of the ball’s velocity at C.
c. / equal in magnitude but opposite in direction to the horizontal component of the ball’s velocity at D.
d. / equal to the horizontal component of its initial velocity.
____ 30. Which of the following is the cause of an acceleration?
a. / speed / c. / forceb. / inertia / d. / velocity
____ 31. What causes a moving object to change direction?
a. / acceleration / c. / inertiab. / velocity / d. / force
____ 32. A newton is equivalent to which of the following quantities?
a. / kg / c. / kg·m/sb. / kg·m/s / d. / kg·(m/s)
____ 33. A free-body diagram represents all of the following except
a. / the object. / c. / forces exerted by the object.b. / forces as vectors. / d. / forces exerted on the object.
____ 34. The free-body diagram shown above represents a car being pulled by a towing cable. In the diagram, the 5800 N force is
a. / the gravitational force acting on the car.b. / the backward force the road exerts on the car.
c. / the upward force the road exerts on the car.
d. / the force exerted by the towing cable on the car.
____ 35. A free-body diagram of a ball falling in the presence of air resistance would show
a. / only a downward arrow to represent the force of air resistance.b. / only a downward arrow to represent the force due to gravity.
c. / a downward arrow to represent the force due to gravity and an upward arrow to represent the force of air resistance.
d. / an upward arrow to represent the force due to gravity and a downward arrow to represent the force of air resistance.
____ 36. Which of the following is the tendency of an object to maintain its state of motion?
a. / acceleration / c. / forceb. / inertia / d. / velocity
____ 37. A late traveler rushes to catch a plane, pulling a suitcase with a force directed 30.0° above the horizontal. If the horizontal component of the force on the suitcase is 60.6 N, what is the force exerted on the handle?
a. / 53.0 N / c. / 65.2 Nb. / 70.0 N / d. / 95.6 N
____ 38. A car goes forward along a level road at constant velocity. The additional force needed to bring the car into equilibrium is
a. / greater than the normal force times the coefficient of static friction.b. / equal to the normal force times the coefficient of static friction.
c. / the normal force times the coefficient of kinetic friction.
d. / zero.
____ 39. If a nonzero net force is acting on an object, then the object is definitely
a. / at rest. / c. / being accelerated.b. / moving with a constant velocity. / d. / losing mass.
____ 40. Which statement about the acceleration of an object is correct?
a. / The acceleration of an object is directly proportional to the net external force acting on the object and inversely proportional to the mass of the object.b. / The acceleration of an object is directly proportional to the net external force acting on the object and directly proportional to the mass of the object.
c. / The acceleration of an object is inversely proportional to the net external force acting on the object and inversely proportional to the mass of the object.
d. / The acceleration of an object is inversely proportional to the net external force acting on the object and directly proportional to the mass of the object.
____ 41. A net force of 6.8 N accelerates a 31 kg scooter across a level parking lot. What is the magnitude of the scooter’s acceleration?
a. / 0.22 m/s / c. / 3.2 m/sb. / 0.69 m/s / d. / 4.6 m/s
____ 42. The statement by Newton that for every action there is an equal but opposite reaction is which of his laws of motion?
a. / first / c. / thirdb. / second / d. / fourth
____ 43. Newton’s third law of motion involves the interactions of
a. / one object and one force. / c. / two object and one force.b. / one object and two forces. / d. / two objects and two forces.
____ 44. A measure of the quantity of matter is
a. / density. / c. / force.b. / weight. / d. / mass.
____ 45. A force does work on an object if a component of the force
a. / is perpendicular to the displacement of the object.b. / is parallel to the displacement of the object.
c. / perpendicular to the displacement of the object moves the object along a path that returns the object to its starting position.
d. / parallel to the displacement of the object moves the object along a path that returns the object to its starting position.
____ 46. Work is done when
a. / the displacement is not zero.b. / the displacement is zero.
c. / the force is zero.
d. / the force and displacement are perpendicular.
____ 47. What is the common formula for work? Assume that W is the work, F is a constant force, v is the change in velocity, and d is the displacement.
a. / W = FDv / c. / W = Fdb. / W = Fd / d. / W = Fd
____ 48. A worker does 25 J of work lifting a bucket, then sets the bucket back down in the same place. What is the total net work done on the bucket?