Exam 1 Review for Physics One (suggested problems) PDF

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Book review questions for the first exam assigned by the instructor of the course. Great review, got an 85% on it!...

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Exam 1 Review Module one 14. • Calculate 1.4+15+7.15+8.003 using the proper number of significant figures. A. 31.553 B. C.

31.550 31.55

D. E.

31.6 32

15. • Calculate 0.688/0.28 using the proper number of significant figures. A. 2.4571 B. 2.457 C. 2.46 D. 2.5 E. 2 16. • Which of the following relationships is dimensionally consistent with a value for acceleration that has dimensions of distance per time per time? In these equations x is distance, t is time, and v is speed. A. υ2/t B. υ/t C. υ/t2 D. υ/x2 E. υ2/x2 31. • Complete the following conversions: A. 125 cm = _______ m B. 233 g = _______ kg C. D. E. F.

786 ms = _______ s 454 kg = _______ mg 208 cm2 = _______ m2 444 m2 = _______ cm2

G. H.

12.5 cm3 = _______ m3 144 m3 = _______ cm3

38. • Give the number of significant figures in each of the following numbers: A. B.

112.4 10

C. D. E.

3.14159 700 1204.0

F. G.

0.0030 9.33×103

H. 0.02240 I. One equation that describes motion of an object is x=vt+x0,

where x is the

position of the object, v is its speed, t is time, and x0 is the initial position. Show that the dimensions in the equation are consistent. J. At a resting pulse rate of 75 beats per minute, the human heart typically pumps about 70 mL of blood per beat. Blood has a density of 1060 kg/m3. Circulating all of the blood in the body through the heart takes about 1 min in a person at rest. (a) How much blood (in L and m3) is in the body? (b) On average, what mass of blood (in g and kg) does the heart pump each beat?

Module Two 16. • Figure 2-23 shows a position versus time graph for a moving object. At which lettered point is the object moving the slowest? A. B.

A B

C. D. E.

C D E SSM

17. • Figure 2-24 shows a position versus time graph for a moving object. At which lettered point is the object moving the fastest? A. A B. B C. C D. D E.

E

18. • A person is driving a car down a straight road. The instantaneous acceleration is constant and in the direction of the car’s motion. The speed of the car is A. B.

increasing. decreasing.

C. D. E.

constant. increasing but will eventually decrease. decreasing but will eventually increase.

19. • A person is driving a car down a straight road. The instantaneous acceleration is constant and directed opposite the direction of the car’s motion. The speed of the car is A. increasing. B. C. D.

decreasing. constant. increasing but will eventually decrease.

E. decreasing but will eventually increase. 20. • A 1-kg ball and a 10-kg ball are dropped from a height of 10 m at the same time. In the absence of air resistance, A. B. C.

the 1-kg ball hits the ground first. the 10-kg ball hits the ground first. the two balls hit the ground at the same time.

D. the 10-kg ball will take 10 times the amount of time to reach the ground. E. there is not enough information to determine which ball hits the ground first. 21. • When throwing a ball straight up, which of the following are correct about the magnitudes of its velocity (v) and its acceleration (a) at the highest point in its path? A. bothv=0 and a=0 B.

v≠0buta=0

C.

v=0buta=9.80m/s2

D.

v≠0buta=9.80m/s2

E. not enough information to determine the velocity (v) and acceleration (a) F. The Olympic record for the marathon set in 2008 is 2 h, 6 min, 32 s. The marathon distance is 26.2 mi. What was the average speed of the record-setting runner in km/h? G. A car traveling at 80.0 km/h is 1500 m behind a truck traveling at 70.0 km/h. How long will it take the car to catch up with the truck? H. The figure below shows an x–t graph for some object. (a) Over what time interval is the acceleration negative? (b) At about what time is the object’s speed the greatest? (c) What is the acceleration between t=4 s

and t=5 s

?

I. Paola can flex her legs from a bent position through a distance of 20.0 cm. Paola leaves the ground when her legs are straight, at a speed of 4.43 m/s. Calculate the magnitude of her acceleration, assuming that it is constant. J. A sperm whale can accelerate at about 0.100 m/s2 when swimming on the surface. How far will a whale travel if it starts at a speed of 1.00 m/s and accelerates to a speed of 2.25 m/s? Assume the whale travels in a straight line K. More people end up in U.S. emergency departments because of fall-related injuries than from any other cause. At what speed would someone hit the ground who accidentally stepped off the top rung of a 6-ft-tall stepladder? (That step is usually embossed with the phrase “Warning! Do not stand on this step.”) Ignore the effects of air resistance.

Module 3 17. • Vector ⇀A

has an x component and a y component that are equal in magnitude. Which

of the following is the angle that vector ⇀A y coordinate system? A. 0° B. 45° C. 60°

makes with respect to the x axis in the same x–

D. 90° E. 120° SSM 18. • The vector in Figure 3-35 has a length of 4.00 units and makes a 30.0° angle with respect to the y axis as shown. What are the x and y components of the vector?

19. • The acceleration of a particle in projectile motion A. points along the parabolic path of the particle. B. is directed horizontally. C. vanishes at the particle’s highest point. D. E.

is vertically downward. is zero.

22. A zookeeper is trying to shoot a monkey sitting at the top of a tree with a tranquilizer gun. If the monkey drops from the tree at the same instant that the zookeeper fires, where should the zookeeper aim if he wants to hit the monkey? (Neglect any effects due to air resistance.) A. Aim straight at the monkey. B. Aim lower than the monkey. C. Aim higher than the monkey. D. Aim to the right of the monkey. E. It’s impossible to determine. 23. • The acceleration vector of a particle in uniform circular motion A. points along the circular path of the particle and in the direction of motion. B. points along the circular path of the particle and opposite the direction of motion. C. is zero. D. points toward the center of the circle. E. points outward from the center of the circle. 24. • If the speed of an object in uniform circular motion remains constant while the radial distance is doubled, the magnitude of the radial acceleration decreases by what factor? A. B. C. D. E.

2 3 4 6 1

25. • You toss a ball into the air at an initial angle 40° from the horizontal. At what point in the ball’s trajectory does the ball have the smallest speed? (Neglect any effects due to air resistance.) A. just after it is tossed B. at the highest point in its flight C.

just before it hits the ground

D. halfway between the ground and the highest point on the rise portion of the trajectory E. halfway between the ground and the highest point on the fall portion of the trajectory F. What are the components Ax and Ay of vector ⇀A in the three coordinate systems shown in Figure 3-38?

37. Given the vector ⇀A with components Ax=2.00 and Ay=6.00, and the vector ⇀B with components Bx=3.00 and Ax=2.00, calculate the magnitude and angle with respect to the +x axis of the vector sum ⇀C=⇀A+⇀B 39. •• Two velocity vectors are given as follows: ⇀A=30m/s, and ⇀B=40m/s, (b) ⇀A−⇀B,

45° north of east

due north. Calculate each of the resultant velocity vectors: (a) ⇀A+⇀B, (c) 2⇀A+⇀B

42. The two vectors shown in Figure 3-40 represent the initial and final velocities of an object during a trip that took 5 s. Calculate the average acceleration during this trip. Is it possible to determine whether the acceleration was uniform from the information given in the problem?

50. A tiger leaps horizontally out of a tree that is 4.00 m high. If he lands 5.00 m from the base of the tree, calculate his initial speed. (Neglect any effects due to air resistance.) 58. We know that the Moon revolves around Earth during a period of 27.3 days. The average distance from the center of Earth to the center of the Moon is 3.84×108 m. What is the acceleration of the Moon due to its motion around Earth?

Module Four 24. The net force on a moving object suddenly becomes zero and remains zero. The object will A. stop abruptly. B. C. D.

reduce speed gradually. continue at constant velocity. increase speed gradually.

E. reduce speed abruptly. 26. • According to Newton’s second law of motion, when a net force acts on an object, the acceleration is A. B. C.

zero. inversely proportional to the object’s mass. independent of mass.

D. E.

inversely proportional to the net force. directly proportional to the object’s mass.

27. • In the absence of a net force, an object can be

A. B.

at rest. in motion with a constant velocity.

C. D. E.

accelerating. at rest or in motion with a constant velocity. It’s not possible to know without more information.

32. How does the magnitude of the normal force exerted by the ramp in Figure 4-25 compare to the weight of the block? The normal force is A. equal to the weight of the block. B. greater than the weight of the block. C. less than the weight of the block. D. possibly equal to or less than the weight of the block, depending on whether or not the ramp surface is smooth. E. possibly greater than or equal to the weight of the block, depending on whether or not the ramp surface is smooth.

46. What is the acceleration of a 2.00×103-kg car if the net force on the car is 4.00×103N? 56. A 1300-kg car is capable of a maximum acceleration of 5.0 m/s2. If this car is required to push a stalled car of mass 1700 kg, what is the maximum magnitude of acceleration of the twocar system? 65. The distance between two telephone poles is 50.0 m. When a 0.500-kg bird lands on the telephone wire midway between the poles, the wire sags 0.15 m. How much tension does the bird produce in the wire? Ignore the weight of the wire

74. •• Two blocks of masses M1 and M2 are connected by a massless string that passes over a massless pulley (Figure 4-33). M2, which has a mass of 20.0 kg, rests on a long ramp of angle θ=30.0°. Friction can be ignored in this problem. (a) What is the value of M1 for which the two blocks are in equilibrium (no acceleration)? (b) If the actual mass of M1 is 5.00 kg and the system is allowed to move, what is the magnitude of the acceleration of the two blocks? (c)

In part (b) does M2 move up or down the ramp? (d) In part (b) how far does block M2 move in 2.00 s?

80. • A 5.0-kg block slides in a straight line. The velocity of the block as a function of time is displayed in the vx–t graph in Figure 4-35. Calculate the net force on the block for the time intervals t = 0 to 1 s, 1 to 3 s, 3 to 5 s, 5 to 6 s, and 6 to 7 s.

92. •• Medical A car traveling at 28.0 m/s hits a bridge abutment. A passenger in the car, who has a mass of 45.0 kg, moves forward a distance of 55.0 cm while being brought to rest by an inflated air bag. Assuming that the force that stops the passenger is constant, what is the magnitude of this force? 21. • A block of mass m slides down a rough incline with constant speed. If a similar block that has a mass of 4m were placed on the same incline, it would A. slide down at the same constant speed. B. accelerate down the incline. C. slowly slide down the incline and then stop. D. slide down with a faster constant speed. E. not move. SSM 25. • A skydiver is falling at his terminal speed. Immediately after he opens his parachute A.

his speed will be larger than his terminal speed.

B. C.

the magnitude of the drag force on the skydiver will decrease. the net force on the skydiver is in the downward direction.

D. E.

the magnitude of the drag force is larger than the skydiver’s weight. the net force on the skydiver is zero

27. • You are on a Ferris wheel moving in a vertical circle. When you are at the bottom of the circle, how does the magnitude of the normal force n exerted by your seat compare to your weight mg? A. n=mg B.

n>mg,

but cannot be exactly calculated without more information.

C.

n...