College Physics Chapter 4 Alan Giambattista Betty Richardson Robert Richardson 4th edition Chapter 4 Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.

Question 1 Car A is traveling with velocity v. Car B is traveling with velocity 2v. The drivers of both cars see a deer in the road ahead and slam on their brakes. How far does car B travel compared to car A before it comes to a stop? Assume each car's brakes can supply the same acceleration. A) one-fourth as far B) half as far C) twice as far D) four times as far

Question 2 Annette throws a snowball horizontally from the top of a roof; Boris throws a snowball straight down. Once in flight, the acceleration of snowball B is ________ the acceleration of snowball A. A) greater than B) less than C) equal to

Question 3 Annette and Boris release their snowballs from the same height and at the same time. Annette's is dropped while Boris' is thrown horizontally. Which one hits the ground first? A) the "dropped" snowball B) the "thrown" snowball C) they hit at the same time D) it depends on how hard Boris threw E) it depends on the initial height

Question 4 In the previous problem, which snowball had the greatest velocity when it hit the ground? A) the "dropped snowball" B) the "thrown snowball" C) they both have the same velocity D) depends on how hard the snowball was thrown

Question 5 You aim at a monkey who is hanging from a tree branch with a tranquilizer gun. At the same instant that you fire the gun, the monkey lets go. Does the tranq hit the monkey? A) Yes, it hits B) Depends on the muzzle velocity C) No, it misses D) Shot is impossible E) Not really sure

Question 6 Which path correctly indicates the motion of the pendulum bob after it is cut at the bottom of its swing? A) B) C)

Question 7 Which path correctly indicates the motion of the pendulum bob when it is cut at the instant it is at the top of its swing? A) B) C) D)

Question 8 When an elevator accelerates upwards, your apparent weight A) increases. B) stays the same. C) decreases.

Question 9 You stand on a scale that rests on the floor of an elevator that is accelerating upward. What is the relationship between the force due to gravity and the normal force exerted by the scale? A) N > mg B) N = mg C) N < mg D) N = 0

Question 10 A parrot that weighs 10 N is sitting on its perch in a birdcage (weight = 7 N), which in turn is sitting on a scale. The parrot launches itself off of its perch to land on a higher platform. What is the reading on the scale when the parrot launches itself off of its perch? A) 7 N B) > 7 N, but < 17 N C) 17 N D) > 17 N

Question 11 A parrot that weighs 10 N is sitting on its perch in a birdcage (weight = 7 N), which in turn is sitting on a scale. The parrot launches itself off of its perch to land on a higher platform. What is the reading on the scale while the parrot is in the air? A) 7 N B) > 7 N, but < 17 N C) 17 N D) > 17 N

Question 12 The following graph shows the positions of two blocks at times 0 s, 1 s, 2 s, and 3 s. What is the relationship between the acceleration of block 1 and block 2? a) 2a1 = a2 b) a1 = a2 c) a1 = 2a2 d) 3a1 = a2 2 4 6 8 10

Question 13 A constant acceleration implies that a) The position of an object changes at a constant rate. b) The speed of an object changes at a constant rate. c) The direction of an object’s motion changes at a constant rate. d) Both c and d are possible.

Question 14 On Friday, Adam heads home for the weekend. He drives for the first two hours at a constant speed of 105 km/hr. The last hour, he drives at a constant speed of 85 km/hr. His average acceleration during the trip was a) 0 m/s2. b) less than 0 m/s2. c) greater than 0 m/s2.

Question 15 On Friday, Adam heads home for the weekend. He drives for the first two hours at a speed of 105 km/hr. The last hour, he drives at a speed of 85 km/hr. His average speed for the trip was a) less than 95 km/hr. b) equal to 95 km/hr. c) greater than 95 km/hr.

Question 16 Which scenario is portrayed by the graph? A) A car starts from rest and accelerates. It then travels at a constant velocity before slowing to a stop. B) A car starts from rest and moves forward. It stops for a while before returning to its starting position. C) A car travels at a constant velocity, then accelerates for a while, then returns to its initial constant velocity.

Question 17 The graph at right represents the velocity of a car over time. The displacement of the car can be found by A) adding the slopes of each section of the graph. B) adding the area 1 to area 2. C) subtracting area 2 from area 1. D) subtracting area 1 from area 2.

Question 18 You drop a rock from an 8th story window. At time t it passes the 7th story window. What window will it be passing at time 2t? Assume the windows are equally spaced. A) 6th story B) 5th story C) 4th story D) 3rd story

Question 19 A rocket on earth is launched at a 45° angle and travels a distance d. On the moon, the same rocket launched at this angle would travel A) a distance greater than d. B) the same distance d. C) a distance less than d.

Question 20 Object 1 with mass m and object 2 with mass 2m, are initially at rest. A force F acts on each of them for a time t. Compare the velocities of the two objects at this time. A) v1 = 1/2 v2 B) v1 = v2 C) v1 = 2v2 D) v1 = 4v2

Answer Key – Chapter 4 D C B A A D B C