PHYSICS CONCEPTUAL QUESTIONS: CH 1, 2, 3

50. A ball is thrown vertically upward from the surface of the earth. Consider the following quantities: (1) the speed of the ball; (2) the velocity of the ball; (3) the acceleration of the ball. Which of these is (are) zero when the ball has reached the maximum height? A) 1 and 2 only B) 1 and 3 only C) 1 only D) 2 only E) 1, 2, and 3

A) 1 and 2 only

53. A race car will make one lap around a circular track of radius R. When the car has traveled halfway around the track, what is the magnitude of the car's displacement from the starting point? A) 2R B) R C) πR D) 2πR E) zero meters

A) 2R

66. Which one of the following statements concerning these vectors is true? A) The vector - has no x component. B) The two vectors have different magnitudes. C) makes a 56° angle with the positive x axis. D) makes a 34° angle with the positive y axis. E) The vector + makes a 34° angle with the positive x axis.

A) The vector - has no x component.

27. In which one of the following cases is the displacement of the object directly proportional to the elapsed time? A) a ball rolls with constant velocity B) a ball at rest is given a constant acceleration C) a ball rolling with velocity vo is given a constant acceleration D) a bead falling through oil experiences a decreasing acceleration E) a rocket fired from the earth's surface experiences an increasing acceleration

A) a ball rolls with constant velocity

is given by: A2 + B2 = C2. Which statement concerning these vectors is true? A) and must be at right angles to each other. B) and could have any orientation relative to each other. C) and must have equal lengths. D) and must be parallel. E) and could be antiparallel.

A) and must be at right angles to each other.

An object is moving along the x axis. The graph shows its position from the starting point as a function of time. Various segments of the graph are identified by the letters A, B, C, and D. 68. During which interval(s) is(are) the object moving in the negative x direction? A) during interval B only B) during intervals B and C C) during intervals C and D D) during intervals B and D

A) during interval B only

26. Which one of the following is not a vector quantity? A) acceleration B) average speed C) displacement D) average velocity E) instantaneous velocity

B) average speed

4. Complete the following statement: Today, the standard unit of time is defined in terms of A) the electromagnetic waves emitted by cesium atoms. B) the motion of the moon around the earth. C) the motion of a precision pendulum. D) the average solar day. E) the speed of light.

A) the electromagnetic waves emitted by cesium atoms.

36. What is the minimum number of vectors with equal magnitudes whose vector sum can be zero? A) two B) three C) four D) five E) six

A) two

A racecar, traveling at constant speed, makes one lap around a circular track of radius r in a time t. Note: The circumference of a circle is given by C = 2πr. 16. When the car has traveled halfway around the track, what is the magnitude of its displacement from the starting point? A) r B) 2r C) πr D) 2πr E) zero meters

B) 2r

2. For which one of the following situations will the path length equal the magnitude of the displacement? A) A toy train is traveling around a circular track. B) A ball is rolling down an inclined plane. C) A train travels 5 miles east before it stops. It then travels 2 miles west. D) A ball rises and falls after being thrown straight up from the earth's surface. E) A ball on the end of a string is moving in a vertical circle.

B) A ball is rolling down an inclined plane.

32. Two objects A and B accelerate from rest with the same constant acceleration. Object A accelerates for twice as much time as object B, however. Which one of the following statements is true concerning these objects at the end of their respective periods of acceleration? A) Object A will travel twice as far as object B. B) Object A will travel four times as far as object B. C) Object A will travel eight times further than object B. D) Object A will be moving four times faster than object B. E) Object A will be moving eight times faster than object B.

B) Object A will travel four times as far as object B.

17. A football is kicked at an angle θ with respect to the horizontal. Which one of the following statements best describes the acceleration of the football during this event if air resistance is neglected? A) The acceleration is zero m/s2 at all times. B) The acceleration is 9.8 m/s2 at all times. C) The acceleration is zero m/s2 when the football has reached the highest point in its trajectory. D) The acceleration is positive as the football rises, and it is negative as the football falls. E) The acceleration starts at 9.8 m/s2 and drops to some constant lower value as the ball approaches the ground.

B) The acceleration is 9.8 m/s2 at all times.

51. A ball is thrown vertically upward from the surface of the earth. The ball rises to some maximum height and falls back toward the surface of the earth. Which one of the following statements concerning this situation is true if air resistance is neglected? A) As the ball rises, its acceleration vector points upward. B) The ball is a freely falling body for the duration of its flight. C) The acceleration of the ball is zero when the ball is at its highest point. D) The speed of the ball is negative while the ball falls back toward the earth. E) The velocity and acceleration of the ball always point in the same direction.

B) The ball is a freely falling body for the duration of its flight.

42. Which statement is true concerning the ball when it is at C, the highest point in its trajectory? A) The ball's velocity and acceleration are both zero. B) The ball's velocity is perpendicular to its acceleration. C) The ball's velocity is not zero, but its acceleration is zero. D) The ball's velocity is zero, but its acceleration is not zero. E) The horizontal and vertical components of the ball's velocity are equal.

B) The ball's velocity is perpendicular to its acceleration.

100. Which one of the following statements best explains why the graph goes through the origin? A) The object was in a vacuum. B) The object was dropped from rest. C) The velocity of the object was constant. D) All v vs. t curves pass through the origin. E) The acceleration of the object was constant.

B) The object was dropped from rest.

5. The mass of a raindrop is 4 milligrams. Which one of the following statements indicates the correct mass of the raindrop in grams? A) The raindrop has a mass of 4 × 106 grams. B) The raindrop has a mass of 4 × 10-3 grams. C) The raindrop has a mass of 4 × 10-1 grams. D) The raindrop has a mass of 4 × 103 grams. E) The raindrop has a mass of 4 × 10-6 grams.

B) The raindrop has a mass of 4 × 10-3 grams.

A tennis ball is thrown upward at an angle from point A. It follows a parabolic trajectory and hits the ground at point D. At the instant shown, the ball is at point B. Point C represents the highest position of the ball above the ground. 40. While in flight, how do the x and y components of the velocity vector of the ball compare at the points B and C? A) The velocity components are non-zero at B and zero at C. B) The x components are the same; the y component at C is zero m/s. C) The x components are the same; the y component has a larger magnitude at C than at B. D) The x component is larger at C than at B; the y component at B points up while at C, it points downward. E) The x component is larger at B than at C; the y component at B points down while at C, it points upward.

B) The x components are the same; the y component at C is zero m/s.

3. Complete the following statement: Today, the standard unit of mass is defined in terms of A) a specified volume of water at 4 °C. B) a standard platinum-iridium cylinder. C) a specified number of cesium atoms. D) a standard platinum bar. E) the speed of light

B) a standard platinum-iridium cylinder.

33. Three vectors , , and add together to yield zero: + + = 0. The vectors and point in opposite directions and their magnitudes are related by the expression: A = 2C. Which one of the following conclusions is correct? A) and have equal magnitudes and point in opposite directions. B) and have equal magnitudes and point in the same direction. C) and have equal magnitudes and point in opposite directions. D) and point in the same direction, but has twice the magnitude of . E) and point in the same direction, but has twice the magnitude of

B) and have equal magnitudes and point in the same direction.

11. Which one of the following pairs of units may not be added together, even after the appropriate unit conversions have been made? A) grams and milligrams B) kilometers and kilograms C) miles and kilometers D) slugs and kilograms E) centimeters and yards

B) kilometers and kilograms

81. During which interval(s) did the object move in the negative x direction? A) only during interval B B) only during interval C C) only during interval D D) during both intervals C and D E) The object never moved in the negative x direction.

B) only during interval C

Two vectors, and , are added together to form the vector = + . The relationship between the magnitudes of these vectors is given by: Cx = 0 Cy = A sin 60° + B sin 30° Ax and Ay point in the positive x and y directions, respectively. 64. Which one of the following statements best describes the orientation of vectors and ? A) and point in opposite directions. B) points 60° above the positive x axis while points 30° above the negative x axis. C) points 60° above the negative x axis while points 30° above the positive x axis. D) points 60° below the positive x axis while points 30° above the positive y axis. E) points 60° below the positive x axis while points 30° below the positive y axis.

B) points 60° above the positive x axis while points 30° above the negative x axis.

35. What is the minimum number of vectors with unequal magnitudes whose vector sum can be zero? A) two B) three C) four D) five E) six

B) three

6. Which one of the following is the longest length? A) 100 meters B) 102 centimeters C) 104 millimeters D) 105 micrometers E) 107 nanometers

C) 104 millimeters

34. What is the angle between the vectors and - when they are drawn from a common origin? A) 0° B) 90° C) 180° D) 270° E) 360°

C) 180°

19. Using the dimensions given for the variables in the table, determine which one of the following expressions is correct. variable dimension f l [L] g A) B) f = 2πgl C) D) E)

C) 2pi= sqrt (g/l)

19. Which one of the following statements concerning this car is true? A) The displacement of the car does not change with time. B) The instantaneous velocity of the car is constant. C) The average speed of the car is the same over any time interval. D) The average velocity of the car is the same over any time interval. E) The average speed of the car over any time interval is equal to the magnitude of the average velocity over the same time interval.

C) The average speed of the car is the same over any time interval.

31. A spring-loaded gun is aimed horizontally and is used to launch identical balls with different initial speeds. The gun is at a fixed position above the floor. The balls are fired one at a time. If the speed of the second ball fired is twice the speed of the first ball fired, how is the horizontal range (denoted R in the figure) affected? A) The range for both balls will be the same. B) The range of the second ball will be half as much as that of the first ball. C) The range of the second ball will be twice as large as that of the first ball. D) The range of the second ball is about 1.4 times larger than that of the first ball. E) The range of the second ball will be smaller than that of the first ball by a factor of 1.4.

C) The range of the second ball will be twice as large as that of the first ball.

Starting from rest, a particle confined to move along a straight line is accelerated at a rate of 4 m/s2. 86. Which statement accurately describes the motion of the particle? A) The particle travels 4 meters during each second. B) The particle travels 4 meters during the first second only. C) The speed of the particle increases by 4 m/s during each second. D) The acceleration of the particle increases by 4 m/s2 during each second. E) The final velocity of the particle will be proportional to the distance that the particle covers.

C) The speed of the particle increases by 4 m/s during each second.

29. Starting from rest, a particle confined to move along a straight line is accelerated at a rate of 5.0 m/s2. Which one of the following statements accurately describes the motion of this particle? A) The particle travels 5.0 m during each second. B) The particle travels 5.0 m only during the first second. C) The speed of the particle increases by 5.0 m/s during each second. D) The acceleration of the particle increases by 5.0 m/s2 during each second. E) The final speed of the particle will be proportional to the distance that the particle covers.

C) The speed of the particle increases by 5.0 m/s during each second.

55. Complete the following statement: According to the observer in the car, the ball will A) follow a parabolic path. B) follow a hyperbolic path. C) follow a path that is straight up and down in the y direction. D) follow a path that is straight across in the +x direction. E) follow a straight line that is angled (less than 90°) with respect to the x direction.

C) follow a path that is straight up and down in the y direction.

66. A bicyclist is riding at a constant speed along a straight-line path. The rider throws a ball straight up to a height a few meters above her head. Ignoring air resistance, where will the ball land? A) behind the rider B) in front of the rider C) in the same hand that threw the ball D) in the opposite hand to the one that threw it E) This cannot be determined without knowing the speed of the rider and the maximum height of the ball.

C) in the same hand that threw the ball

60. Two vectors and , are added together to form the vector = + . The relationship between the magnitudes of these vectors is given by: Cx = A cos 30° + B and Cy = -A sin 30°. Which statement best describes the orientation of these vectors? A) points in the negative x direction while points in the positive y direction. B) points in the negative y direction while points in the positive x direction. C) points 30° below the positive x axis while points in the positive x direction. D) points 30° above the positive x axis while points in the positive x direction. E) points 30° above the negative x axis while points in the positive x direction.

C) points 30° below the positive x axis while points in the positive x direction.

1. A particle travels along a curved path between two points P and Q as shown. The displacement of the particle does not depend on A) the location of P. B) the location of Q. C) the distance traveled from P to Q. D) the shortest distance between P and Q. E) the direction of Q from P.

C) the distance traveled from P to Q.

29. Which one of the following quantities is a vector quantity? A) the age of the earth B) the mass of a freight train C) the earth's pull on your body D) the temperature of an iced coffee E) the number of people attending a soccer game

C) the earth's pull on your body

3. Which one of the physical quantities listed below is not correctly paired with its SI unit and dimension? Quantity Unit Dimension A) velocity m/s [L]/[T] B) path length m [L] C) speed m/s [L]/[T] D) displacement m/s2 [L]/[T]2 E) speed × time m [L]

D) displacement m/s2 [L]/[T]2

10. Which one of the following choices is equivalent to 8.0 m2? A) 8.0 × 10-4 cm2 B) 8.0 × 102 cm2 C) 8.0 × 10-2 cm2 D) 8.0 × 104 cm2 E) 8.0 × 103 cm2

D) 8.0 × 104 cm2

30. Which one of the following situations is not possible? A) A body has zero velocity and non-zero acceleration. B) A body travels with a northward velocity and a northward acceleration. C) A body travels with a northward velocity and a southward acceleration. D) A body travels with a constant velocity and a time-varying acceleration. E) A body travels with a constant acceleration and a time-varying velocity.

D) A body travels with a constant velocity and a time-varying acceleration.

50. Which one of the following statements concerning vectors and scalars is false? A) In calculations, the vector components of a vector may be used in place of the vector itself. B) It is possible to use vector components that are not perpendicular. C) A scalar component may be either positive or negative. D) A vector that is zero may have components other than zero. E) Two vectors are equal only if they have the same magnitude and direction.

D) A vector that is zero may have components other than zero.

49. Ball A is dropped from rest from a window. At the same instant, ball B is thrown downward; and ball C is thrown upward from the same window. Which statement concerning the balls after their release is necessarily true if air resistance is neglected? A) At some instant after it is thrown, the acceleration of ball C is zero. B) All three balls strike the ground at the same time. C) All three balls have the same velocity at any instant. D) All three balls have the same acceleration at any instant. E) All three balls reach the ground with the same velocity.

D) All three balls have the same acceleration at any instant.

79. Which segment(s) of the graph represent(s) a constant velocity of +1.0 m/s? A) A B) B C) C D) D E) A and C

D) D

20. In which one of the following situations does the car have a westward acceleration? A) The car travels westward at constant speed. B) The car travels eastward and speeds up. C) The car travels westward and slows down. D) The car travels eastward and slows down. E) The car starts from rest and moves toward the east.

D) The car travels eastward and slows down.

35. An object moving along a straight line is decelerating. Which one of the following statements concerning the object's acceleration is necessarily true? A) The value of the acceleration is positive. B) The direction of the acceleration is in the same direction as the displacement. C) An object that is decelerating has a negative acceleration. D) The direction of the acceleration is in the direction opposite to that of the velocity. E) The acceleration changes as the object moves along the line.

D) The direction of the acceleration is in the direction opposite to that of the velocity.

66. Starting from rest, a particle that is confined to move along a straight line is accelerated at a rate of 5.0 m/s2. Which statement concerning the slope of the position versus time graph for this particle is true? A) The slope has a constant value of 5.0 m/s. B) The slope has a constant value of 5.0 m/s2. C) The slope is both constant and negative. D) The slope is not constant and increases with increasing time. E) The slope is not constant and decreases with increasing time.

D) The slope is not constant and increases with increasing time.

18. A baseball is hit upward and travels along a parabolic arc before it strikes the ground. Which one of the following statements is necessarily true? A) The acceleration of the ball decreases as the ball moves upward. B) The velocity of the ball is zero m/s when the ball is at the highest point in the arc. C) The acceleration of the ball is zero m/s2 when the ball is at the highest point in the arc. D) The x-component of the velocity of the ball is the same throughout the ball's flight. E) The velocity of the ball is a maximum when the ball is at the highest point in the arc.

D) The x-component of the velocity of the ball is the same throughout the ball's flight.

28. Which one of the following statements must be true if the expression is to be used? A) x is constant. B) v is constant. C) t is constant. D) a is constant. E) Both v0 and t are constant.

D) a is constant.

31. Two vectors and are added together to form a vector . The relationship between the magnitudes of the vectors is given by A + B = C. Which one of the following statements concerning these vectors is true? A) and must be displacements. B) and must have equal lengths. C) and must point in opposite directions. D) and must point in the same direction. E) and must be at right angles to each other.

D) and must point in the same direction.

28. Which one of the following choices is a vector quantity? A) mass B) temperature C) time D) displacement E) volume

D) displacement

39. A bullet is aimed at a target on the wall a distance L away from the firing position. Because of gravity, the bullet strikes the wall a distance Δy below the mark as suggested in the figure. Note: The drawing is not to scale. If the distance L was half as large and the bullet had the same initial velocity, how would Δy be affected? A) Δy will double. B) Δy will be half as large. C) Δy will be four times larger. D) Δy will be one fourth as large. E) Δy is not possible to determine unless numerical values are given for the distances.

D) Δy will be one fourth as large.

9. Complete the following statement: The ratio is equal to A) 102. B) 103. C) 106. D) 10-3. E) 10-6.

E) 10-6.

23. Three sticks are arranged to form a right triangle. If the lengths of the three sticks are 0.47 m, 0.62 m and 0.78 m, what are the three angles of the triangle? A) 90°, 45°, and 45° B) 90°, 62°, and 28° C) 90°, 59°, and 31° D) 90°, 48°, and 42° E) 90°, 53°, and 37°

E) 90°, 53°, and 37°

71. In which segment(s) of the graph does the object's average velocity (measured from t = 0 s) decrease with time? A) AB only B) BC only C) DE only D) AB and CD E) BC and DE

E) BC and DE

33. Two cars travel along a level highway. It is observed that the distance between the cars is increasing. Which one of the following statements concerning this situation is necessarily true? A) The velocity of each car is increasing. B) At least one of the cars has a non-zero acceleration. C) The leading car has the greater acceleration. D) The trailing car has the smaller acceleration. E) Both cars could be accelerating at the same rate.

E) Both cars could be accelerating at the same rate.

37. A physics student adds two displacement vectors with magnitudes of 8.0 km and 6.0 km. Which one of the following statements is true concerning the magnitude of the resultant displacement? A) It must be 10.0 km. B) It must be 14.0 km. C) It could be equal to zero kilometers, depending on how the vectors are oriented. D) No conclusion can be reached without knowing the directions of the vectors. E) It could have any value between 2.0 km and 14.0 km depending on how the vectors are oriented

E) It could have any value between 2.0 km and 14.0 km depending on how the vectors are oriented

43. At which point is the velocity vector changing most rapidly with time? A) A B) B C) C D) D E) It is changing at the same rate at all four points.

E) It is changing at the same rate at all four points.

30. Which one of the following statements is true concerning scalar quantities? A) Scalar quantities must be represented by base units. B) Scalar quantities have both magnitude and direction. C) Scalar quantities can be added to vector quantities using rules of trigonometry. D) Scalar quantities can be added to other scalar quantities using rules of trigonometry. E) Scalar quantities can be added to other scalar quantities using rules of ordinary addition.

E) Scalar quantities can be added to other scalar quantities using rules of ordinary addition.

4. A car travels in a straight line covering a total distance of 90.0 miles in 60.0 minutes. Which one of the following statements concerning this situation is necessarily true? A) The velocity of the car is constant. B) The acceleration of the car must be non-zero. C) The first 45 miles must have been covered in 30.0 minutes. D) The speed of the car must be 90.0 miles per hour throughout the entire trip. E) The average velocity of the car is 90.0 miles per hour in the direction of motion.

E) The average velocity of the car is 90.0 miles per hour in the direction of motion.

41. While in flight, how do the x and y components of the velocity vector of the ball compare at the points A and D? A) The velocity components are non-zero at A and are zero m/s at D. B) The velocity components are the same in magnitude and direction at both points. C) The velocity components have the same magnitudes at both points, but their directions are reversed. D) The velocity components have the same magnitudes at both points, but the directions of the x components are reversed. E) The velocity components have the same magnitudes at both points, but the directions of the y components are reversed.

E) The velocity components have the same magnitudes at both points, but the directions of the y components are reversed.

63. A passenger at rest on a flatbed train car fires a bullet straight up. The event is viewed by observers at rest on the station platform as the train moves past the platform with constant velocity. What is the trajectory of the bullet as described by the observers on the platform? A) a straight horizontal path in the direction of the train's velocity B) a straight vertical path up and down C) a circular path centered on the gun D) a straight diagonal path E) a parabolic path

E) a parabolic path

103. If the same object were released in air, the magnitude of its acceleration would begin at the free-fall value, but it would decrease continuously to zero as the object continued to fall. For which one of the choices given does the solid line best represent the speed of the object as a function of time when it is dropped from rest in air? Note: The dashed line shows the free-fall under vacuum graph for comparison. A) a B) b C) c D) d E) e

E) e

1. Which one of the following is an SI base unit? A) gram B) slug C) newton D) centimeter E) kilogram

E) kilogram

2. Complete the following statement: Today, the standard meter is defined in terms of A) the distance from the earth's equator to the north pole. B) the wavelength of light emitted from a krypton atom. C) the wavelength of light emitted from a sodium atom. D) a platinum-iridium bar kept in France. E) the speed of light.

E) the speed of light.

18. The distance d that a certain particle moves may be calculated from the expression d = at + bt2 where a and b are constants; and t is the elapsed time. What must the dimensions of the quantities a and b be, respectively? A) B) [L], [L]2 C) D) E)

[L]/[T] AND [L]/[T]2

17. The mathematical relationship between three physical quantities is given by . If the dimension of b is; and the dimension of c is [L]. Which one of the following choices is the dimension of a? A) [L] B) C) D) [T] E)

[L]/[T]2