What do you want to know? 1. nothing 2. everything

Transcription

1 What do you want to know? 1. nothing 2. everything

2 What do you want to know? 1. nothing 2. everything

3 An airtight box has a pressure inside of zero. It is sealed and taken up a mountain where the pressure outside is P a. The area of the lid is 0.013m 2. What force do you have to apply lift the lid? N N N N

4 An airtight box has a pressure inside of zero. It is sealed and taken up a mountain where the pressure outside is P a. The area of the lid is 0.013m 2. What force do you have to apply lift the lid? N N N N

5 A submersible pump is put underwater in a well and used to push water up a pipe. What is the minimum pressure the pump must be able to create to raise water to a height of 71m? Density of water is 1, 000kg/m P a P a P a P a P a 6. Voltron

6 A submersible pump is put underwater in a well and used to push water up a pipe. What is the minimum pressure the pump must be able to create to raise water to a height of 71m? Density of water is 1, 000kg/m P a P a P a P a P a 6. Voltron

7 Human lungs work well as long as the pressure difference between inside and outside is 1/20 an atmosphere. To what depth can someone with a long snorkel dive if the density of sea water is 1025 kg/m 3? m m m m

8 Human lungs work well as long as the pressure difference between inside and outside is 1/20 an atmosphere. To what depth can someone with a long snorkel dive if the density of sea water is 1025 kg/m 3? m m m m

9 The density of the Sun is 1400 kg/m 3. Will the Sun sink or float in water? 1. Sink 2. Float 3. Boil

10 The density of the Sun is 1400 kg/m 3. Will the Sun sink or float in water? 1. Sink 2. Float 3. Boil

11 Wind blows across your roof at 15 m/s. The density of air is 1.29 kg/m 3. Determine the reduction of pressure between this air and stationary air Pa Pa Pa Pa Pa

12 Wind blows across your roof at 15 m/s. The density of air is 1.29 kg/m 3. Determine the reduction of pressure between this air and stationary air Pa Pa Pa Pa Pa

13 A hand exerciser uses a spring. A force of 89N is required to compress the spring by m. Determine the force needed to compress the spring by m N N N 4. 5N 5. 1B 6. 10,000N

14 A hand exerciser uses a spring. A force of 89N is required to compress the spring by m. Determine the force needed to compress the spring by m N N N 4. 5N 5. 1B 6. 10,000N

15 A human eardrum vibrates about its equilibrium position. This vibration has an amplitude of m and a max speed of m/s. What is the frequency of the vibration? Hz Hz Hz Hz Hz Hz

16 A human eardrum vibrates about its equilibrium position. This vibration has an amplitude of m and a max speed of m/s. What is the frequency of the vibration? Hz Hz Hz Hz Hz Hz

17 You are bouncing on your bed and always staying in contact with it. This creates simple harmonic motion and takes 1.9s to complete one cycle. The height of each bounce is 45cm. Determine the amplitude m m m 4. 45m m 6. 7 yeards

18 You are bouncing on your bed and always staying in contact with it. This creates simple harmonic motion and takes 1.9s to complete one cycle. The height of each bounce is 45cm. Determine the amplitude m m m 4. 45m m 6. 7 yeards

19 You are bouncing on your bed and always staying in contact with it. This creates simple harmonic motion and takes 1.9s to complete one cycle. The height of each bounce is 45cm. Determine the angular frequency rad/s m/s 3. 5rad/s 4. 5m/s rad/s

20 You are bouncing on your bed and always staying in contact with it. This creates simple harmonic motion and takes 1.9s to complete one cycle. The height of each bounce is 45cm. Determine the angular frequency rad/s m/s 3. 5rad/s 4. 5m/s rad/s

21 You are bouncing on your bed and always staying in contact with it. This creates simple harmonic motion and takes 1.9s to complete one cycle. The height of each bounce is 45cm. Determine the maximum speed you experience m/s 2. 2m/s 3. 5m/s 4. 1m/s 5. 0m/s rad/s

22 You are bouncing on your bed and always staying in contact with it. This creates simple harmonic motion and takes 1.9s to complete one cycle. The height of each bounce is 45cm. Determine the maximum speed you experience m/s 2. 2m/s 3. 5m/s 4. 1m/s 5. 0m/s rad/s

23 A pen contains a spring with a spring constant of 250N/m. When the tip of the pen is retracted the spring is compressed by 5mm from its unscratched length. To push the tip into the locked position, you must compress the spring an additional 6mm. How much work is done by the spring force to extend the tip? J N J Nm kg

24 A pen contains a spring with a spring constant of 250N/m. When the tip of the pen is retracted the spring is compressed by 5mm from its unscratched length. To push the tip into the locked position, you must compress the spring an additional 6mm. How much work is done by the spring force to extend the tip? J N J Nm kg

25 A 49N weight is attached to your foot and is extended at an angle θ. When θ is 90 degrees, what is the magnitude of the torque exerted if your leg is.55m long Nm 2. 20Nm 3. 29Nm 4. 27Nm 5. 30Nm 6. 32Nm

26 A 49N weight is attached to your foot and is extended at an angle θ. When θ is 90 degrees, what is the magnitude of the torque exerted if your leg is.55m long Nm 2. 20Nm 3. 29Nm 4. 27Nm 5. 30Nm 6. 32Nm

27 Dude stands on the floor. His upper body weighs 438N and has a center of gravity 1.28m above the floor. His middle body has a weight of 144N and a center of gravity 0.76m above the floor. His lower body has a weight of 87N and a center of gravity 0.25m above the floor. Find the location of his center of his entire bodies center of gravity m m m m J

28 Dude stands on the floor. His upper body weighs 438N and has a center of gravity 1.28m above the floor. His middle body has a weight of 144N and a center of gravity 0.76m above the floor. His lower body has a weight of 87N and a center of gravity 0.25m above the floor. Find the location of his center of his entire bodies center of gravity m m m m J

29 In an isometric exercise a person places a hand on a scale and pushes vertically down, keeping the forearm horizontal. The forearm weighs 22N and has a center of gravity.15m from the elbow. The scale registers 111N and is.3m from the elbow. The muscle attaches m from the elbow. Find the magnitude of the muscle force N N N N 5. 65N

30 In an isometric exercise a person places a hand on a scale and pushes vertically down, keeping the forearm horizontal. The forearm weighs 22N and has a center of gravity.15m from the elbow. The scale registers 111N and is.3m from the elbow. The muscle attaches m from the elbow. Find the magnitude of the muscle force N N N N 5. 65N

31 Calculate the rotational kinetic energy of Earth based on its rotation around its axis. M = kg, r = m, I = 2/5mr J J J J J

32 Calculate the rotational kinetic energy of Earth based on its rotation around its axis. M = kg, r = m, I = 2/5mr J J J J J

33 A curveball takes 0.6s to reach the catcher. If it spins with an angular velocity of 330 rev/min, what is the angular displacement of the ball? 1. 19rad 2. 21rad 3. 23rad 4. 25rad rad

34 A curveball takes 0.6s to reach the catcher. If it spins with an angular velocity of 330 rev/min, what is the angular displacement of the ball? 1. 19rad 2. 21rad 3. 23rad 4. 25rad rad

35 The shaft of a pump starts from rest and has an angular acceleration of 3.00rad/s 2 for 18s. At the end of this time what is the shafts angular speed? 1. 98rad/s 2. 75rad/s 3. 54rad/s 4. 33rad/s 5. 22rad/s 6. 1rad/s

36 The shaft of a pump starts from rest and has an angular acceleration of 3.00rad/s 2 for 18s. At the end of this time what is the shafts angular speed? 1. 98rad/s 2. 75rad/s 3. 54rad/s 4. 33rad/s 5. 22rad/s 6. 1rad/s

37 A fan blade rotates with constant angular acceleration of 12rad/s 2. at what point on the blade measured from the axis of rotation, does the tangential acceleration equal the acceleration due to gravity? m m m m m

38 A fan blade rotates with constant angular acceleration of 12rad/s 2. at what point on the blade measured from the axis of rotation, does the tangential acceleration equal the acceleration due to gravity? m m m m m

39 You are currently riding a stationary bike. 1. True 2. False

40 You are currently riding a stationary bike. 1. True 2. False

41 You are riding a stationary bike which tells you the wheel is spinning at 9.1rad/s. If you ride for 35min, how far would you have traveled if you went out in the real world to bike instead of staying inside? The radius of the bike is 0.45m m 2. 86km cm 4. 5 lifetimes years 6. 8 days

42 You are riding a stationary bike which tells you the wheel is spinning at 9.1rad/s. If you ride for 35min, how far would you have traveled if you went out in the real world to bike instead of staying inside? The radius of the bike is 0.45m m 2. 86km cm 4. 5 lifetimes years 6. 8 days

43 A car takes 9.0s to accelerate from rest to 27m/s. find the average force that acts on the car if it has a mass of 1400kg N N N 4. 30N N N

44 A car takes 9.0s to accelerate from rest to 27m/s. find the average force that acts on the car if it has a mass of 1400kg N N N 4. 30N N N

45 A volleyball is spiked so that it s incoming velocity of 4.0 m/s is changed to an outgoing velocity of -21 m/s. If the ball has mass of 0.35kg, what is the impulse the player applies s kg m s kg m s kg kg m s

46 A volleyball is spiked so that it s incoming velocity of 4.0 m/s is changed to an outgoing velocity of -21 m/s. If the ball has mass of 0.35kg, what is the impulse the player applies s kg m s kg m s kg kg m s

47 In a footieball game, a receiver is standing still having just caught the ball. Before he can move, a tackler, running with velocity +4.5 m/s grabs him. The tackler holds onto the receiver and the two move off together with a velocity of +2.6 m/s. the mass of the tackler is 115 kg. What type of collision is this? 1. Elastic 2. Inelastic 3. Forever 4. Loving 5. Sad

48 In a footieball game, a receiver is standing still having just caught the ball. Before he can move, a tackler, running with velocity +4.5 m/s grabs him. The tackler holds onto the receiver and the two move off together with a velocity of +2.6 m/s. the mass of the tackler is 115 kg. What type of collision is this? 1. Elastic 2. Inelastic 3. Forever 4. Loving 5. Sad

49 In a footieball game, a receiver is standing still having just caught the ball. Before he can move, a tackler, running with velocity +4.5 m/s grabs him. The tackler holds onto the receiver and the two move off together with a velocity of +2.6 m/s. the mass of the tackler is 115 kg. Assuming momentum is conserved, find the mass of the receiver Kg 2. 84Kg 3. 94Kg Kg 5. 9Kg

50 In a footieball game, a receiver is standing still having just caught the ball. Before he can move, a tackler, running with velocity +4.5 m/s grabs him. The tackler holds onto the receiver and the two move off together with a velocity of +2.6 m/s. the mass of the tackler is 115 kg. Assuming momentum is conserved, find the mass of the receiver Kg 2. 84Kg 3. 94Kg Kg 5. 9Kg

51 A 2 stage rocket moves in space at a constant velocity of 4900m/s. the 2 stages are then seperated by a small explosion between them. Immediately after the explosion the velocity of the 1200kg upper stage is 5700m/s in the same direction. What is the final velocity of the lower 2400kg stage? 1. 0m/s m/s m/s m/s m/s m/s

52 A 2 stage rocket moves in space at a constant velocity of 4900m/s. the 2 stages are then seperated by a small explosion between them. Immediately after the explosion the velocity of the 1200kg upper stage is 5700m/s in the same direction. What is the final velocity of the lower 2400kg stage? 1. 0m/s m/s m/s m/s m/s m/s

53 A car mass 1100kg is traveling at 32 m/s when it collides head on with an suv mass 2500kg. They stop together. What was the suvs initial speed? 1. 5m/s m/s 3. 14m/s m/s 5. 21m/s m/s

54 A car mass 1100kg is traveling at 32 m/s when it collides head on with an suv mass 2500kg. They stop together. What was the suvs initial speed? 1. 5m/s m/s 3. 14m/s m/s 5. 21m/s m/s

55 A cue ball m=0.165kg, is at rest on a table. It is struck by a stick in the center with an impulse of 1.5 Ns. The ball then strikes another ball of equal mass perfecly elastically. What is the velocity of the second ball? m/s m/s m/s m/s

56 A cue ball m=0.165kg, is at rest on a table. It is struck by a stick in the center with an impulse of 1.5 Ns. The ball then strikes another ball of equal mass perfecly elastically. What is the velocity of the second ball? m/s m/s m/s m/s

57 A cable lifts a 1200kg car at a constant velocity for a distance of 35m. What is the work done by the tension in the cable? ,000J ,000J ,000J ,000J

58 A cable lifts a 1200kg car at a constant velocity for a distance of 35m. What is the work done by the tension in the cable? ,000J ,000J ,000J ,000J

59 185,000J accelerate a car from 23m/s to 28m/s. What is the cars mass? Kg Kg Kg Kg

60 185,000J accelerate a car from 23m/s to 28m/s. What is the cars mass? Kg Kg Kg Kg

61 A shot putter throws a shot (weight 71.1N) that leaves his hand at a distance of 1.52m above the ground. How much works is done by gravity when the ball is 2.13m above the ground J J J J 5. 15J J

62 A shot putter throws a shot (weight 71.1N) that leaves his hand at a distance of 1.52m above the ground. How much works is done by gravity when the ball is 2.13m above the ground J J J J 5. 15J J

63 One kilowatt hour is the amount of work or energy generated when one kilowatt of power is supplied for a time of one hour. Determine the number of joules of energy in one kilowatt hour J J J J J 6. 6J

64 One kilowatt hour is the amount of work or energy generated when one kilowatt of power is supplied for a time of one hour. Determine the number of joules of energy in one kilowatt hour J J J J J 6. 6J

65 A concrete block is pulled 7.0 m across a frictionless surface by means of a rope. The tension in the rope is 40 N; and the net work done on the block is 247 J. What angle does the rope make with the horizontal?

66 A concrete block is pulled 7.0 m across a frictionless surface by means of a rope. The tension in the rope is 40 N; and the net work done on the block is 247 J. What angle does the rope make with the horizontal?

67 Mike is cutting the grass using a human-powered lawn mower. He pushes the mower with a force of 45 N directed at an angle of 41 below the horizontal direction. Calculate the work that Mike does on the mower each time he pushes it 9.1 m across the yard J J J J J

68 Mike is cutting the grass using a human-powered lawn mower. He pushes the mower with a force of 45 N directed at an angle of 41 below the horizontal direction. Calculate the work that Mike does on the mower each time he pushes it 9.1 m across the yard J J J J J

69 A 1.0-kg ball on the end of a string is whirled at a constant speed of 2.0 m/s in a horizontal circle of radius 1.5 m. What is the work done by the centripetal force during one revolution? 1. zero joules J J J J

70 A 1.0-kg ball on the end of a string is whirled at a constant speed of 2.0 m/s in a horizontal circle of radius 1.5 m. What is the work done by the centripetal force during one revolution? 1. zero joules J J J J

71 Larry s gravitational potential energy is 1870 J as he sits 2.20 m above the ground in a sky diving airplane before it takes off. What is Larry s gravitational potential energy when be begins to jump from the airplane at an altitude of 923 m? J J J J J

72 Larry s gravitational potential energy is 1870 J as he sits 2.20 m above the ground in a sky diving airplane before it takes off. What is Larry s gravitational potential energy when be begins to jump from the airplane at an altitude of 923 m? J J J J J

73 Which one of the following choices is an example of a conservative force? 1. tension 2. normal force 3. static frictional force 4. elastic spring force

74 Which one of the following choices is an example of a conservative force? 1. tension 2. normal force 3. static frictional force 4. elastic spring force

75 A pebble rolls off the roof of Science Hall and falls vertically. Just before it reaches the ground, the pebble s speed is 17 m/s. Neglect air resistance and determine the height of Science Hall m m m m m

76 A pebble rolls off the roof of Science Hall and falls vertically. Just before it reaches the ground, the pebble s speed is 17 m/s. Neglect air resistance and determine the height of Science Hall m m m m m

77 A bicyclist is traveling at a speed of 20.0 m/s as he approaches the bottom of a hill. He decides to coast up the hill and stops upon reaching the top. Neglecting friction, determine the vertical height of the hill m m m m m

78 A bicyclist is traveling at a speed of 20.0 m/s as he approaches the bottom of a hill. He decides to coast up the hill and stops upon reaching the top. Neglecting friction, determine the vertical height of the hill m m m m m

79 An engineer is asked to design a playground slide such that the speed a child reaches at the bottom does not exceed 6.0 m/s. Determine the maximum height that the slide can be m m m m m

80 An engineer is asked to design a playground slide such that the speed a child reaches at the bottom does not exceed 6.0 m/s. Determine the maximum height that the slide can be m m m m m

81 A physics student shoves a 0.50-kg block from the bottom of a frictionless 30.0 inclined plane. The student performs 4.0 J of work and the block slides a distance s along the incline before it stops. Determine the value of s cm cm cm cm cm

82 A physics student shoves a 0.50-kg block from the bottom of a frictionless 30.0 inclined plane. The student performs 4.0 J of work and the block slides a distance s along the incline before it stops. Determine the value of s cm cm cm cm cm

83 An automobile approaches a barrier at a speed of 20 m/s along a level road. The driver locks the brakes at a distance of 50 m from the barrier. What minimum coefficient of kinetic friction is required to stop the automobile before it hits the barrier?

84 An automobile approaches a barrier at a speed of 20 m/s along a level road. The driver locks the brakes at a distance of 50 m from the barrier. What minimum coefficient of kinetic friction is required to stop the automobile before it hits the barrier?

85 An escalator is 30.0 meters long and slants at 30.0 relative to the horizontal. If it moves at 1.00 m/s, at what rate does it do work in lifting a 50.0-kg woman from the bottom to the top of the escalator? W W W W W

86 An escalator is 30.0 meters long and slants at 30.0 relative to the horizontal. If it moves at 1.00 m/s, at what rate does it do work in lifting a 50.0-kg woman from the bottom to the top of the escalator? W W W W W

87 A warehouse worker uses a forklift to raise a crate of pickles on a platform to a height 2.75 m above the floor. The combined mass of the platform and the crate is 207 kg. If the power expended by the forklift is 1440 W, how long does it take to lift the crate? s s s s s

88 A warehouse worker uses a forklift to raise a crate of pickles on a platform to a height 2.75 m above the floor. The combined mass of the platform and the crate is 207 kg. If the power expended by the forklift is 1440 W, how long does it take to lift the crate? s s s s s

89 The second hand on a watch has a length of 4.50 mm and makes one revolution in s. What is the speed of the end of the second hand as it moves in uniform circular motion? m/s m/s m/s m/s m/s

90 The second hand on a watch has a length of 4.50 mm and makes one revolution in s. What is the speed of the end of the second hand as it moves in uniform circular motion? m/s m/s m/s m/s m/s

91 A car traveling at 20 m/s follows a curve in the road so that its centripetal acceleration is 5m/s 2. What is the radius of the curve? 1. 4 m 2. 8 m m m m

92 A car traveling at 20 m/s follows a curve in the road so that its centripetal acceleration is 5m/s 2. What is the radius of the curve? 1. 4 m 2. 8 m m m m

93 A satellite is placed in a circular orbit to observe the surface of Mars from an altitude of 144 km. The equatorial radius of Mars is 3397 km. If the speed of the satellite is 3480 m/s, what is the magnitude of the centripetal acceleration of the satellite? m/s m/s m/s m/s m/s 2

94 A satellite is placed in a circular orbit to observe the surface of Mars from an altitude of 144 km. The equatorial radius of Mars is 3397 km. If the speed of the satellite is 3480 m/s, what is the magnitude of the centripetal acceleration of the satellite? m/s m/s m/s m/s m/s 2

95 A 0.25-kg ball attached to a string is rotating in a horizontal circle of radius 0.5 m. If the ball revolves twice every second, what is the tension in the string? 1. 2 N 2. 5 N 3. 7 N N N

96 A 0.25-kg ball attached to a string is rotating in a horizontal circle of radius 0.5 m. If the ball revolves twice every second, what is the tension in the string? 1. 2 N 2. 5 N 3. 7 N N N

97 Holly puts a box into the trunk of her car. Later, she drives around an unbanked curve that has a radius of 48 m. The speed of the car on the curve is 16 m/s, but the box remains stationary relative to the floor of the trunk. Determine the minimum coefficient of static friction for the box on the floor of the trunk This cannot be determined without knowing the mass of the box.

98 Holly puts a box into the trunk of her car. Later, she drives around an unbanked curve that has a radius of 48 m. The speed of the car on the curve is 16 m/s, but the box remains stationary relative to the floor of the trunk. Determine the minimum coefficient of static friction for the box on the floor of the trunk This cannot be determined without knowing the mass of the box.

99 A space station is designed in the shape of a large, hollow donut that is uniformly rotating. The outer radius of the station is 350 m. With what period must the station rotate so that a person sitting on the outer wall experiences artificial gravity, i.e. an acceleration of 9.8m/s 2? s s s s s

100 A space station is designed in the shape of a large, hollow donut that is uniformly rotating. The outer radius of the station is 350 m. With what period must the station rotate so that a person sitting on the outer wall experiences artificial gravity, i.e. an acceleration of 9.8m/s 2? s s s s s

101 A plane is traveling at 200 m/s following the arc of a vertical circle of radius R. At the top of its path, the passengers experience weightlessness. To one significant figure, what is the value of R? m m m m m

102 A plane is traveling at 200 m/s following the arc of a vertical circle of radius R. At the top of its path, the passengers experience weightlessness. To one significant figure, what is the value of R? m m m m m

103 When the net force that acts on a hockey puck is 12 N, the puck accelerates at a rate of 48 m/s2. Determine the mass of the puck kg kg kg kg kg

104 When the net force that acts on a hockey puck is 12 N, the puck accelerates at a rate of 48 m/s2. Determine the mass of the puck kg kg kg kg kg

105 A net force of 25 N is applied for 5.7 s to a 12 kg box initially at rest. What is the speed of the box at the end of the 5.7-s interval? m/s m/s m/s m/s m/s

106 A net force of 25 N is applied for 5.7 s to a 12 kg box initially at rest. What is the speed of the box at the end of the 5.7-s interval? m/s m/s m/s m/s m/s

107 A 975-kg car accelerates from rest to 26.7 m/s in a distance of 120 m. What is the magnitude of the average net force acting on the car? N N N N N

108 A 975-kg car accelerates from rest to 26.7 m/s in a distance of 120 m. What is the magnitude of the average net force acting on the car? N N N N N

109 Two forces act on a 16-kg object. The first force has a magnitude of 68 N and is directed 24 north of east. The second force is 32 N, 48 north of west. What is the acceleration of the object resulting from the application of these two forces to the object? m/s 2, 5.5 north of east m/s 2, 18 north of west m/s 2, 34 north of east m/s 2, 5.5 north of west m/s 2, 52 north of east

110 Two forces act on a 16-kg object. The first force has a magnitude of 68 N and is directed 24 north of east. The second force is 32 N, 48 north of west. What is the acceleration of the object resulting from the application of these two forces to the object? m/s 2, 5.5 north of east m/s 2, 18 north of west m/s 2, 34 north of east m/s 2, 5.5 north of west m/s 2, 52 north of east

111 What is the weight of a 2.50-kg bag of sand on the surface of the earth? N N N N N

112 What is the weight of a 2.50-kg bag of sand on the surface of the earth? N N N N N

113 A 2.00-kg projectile is fired at an angle of What is the magnitude of the force exerted on the projectile when it is at the highest position in its trajectory? Neglect any effects of air resistance N N N N 5. 0 N

114 A 2.00-kg projectile is fired at an angle of What is the magnitude of the force exerted on the projectile when it is at the highest position in its trajectory? Neglect any effects of air resistance N N N N 5. 0 N

115 The wheels of an automobile are locked as it slides to a stop from an initial speed of 30.0 m/s. If the coefficient of kinetic friction is and the road is horizontal, approximately how long does it take the car to stop? s s s s s

116 The wheels of an automobile are locked as it slides to a stop from an initial speed of 30.0 m/s. If the coefficient of kinetic friction is and the road is horizontal, approximately how long does it take the car to stop? s s s s s

117 A boy pulls a 5.0-kg sled with a rope that makes a 60.0 angle with respect to the horizontal surface of a frozen pond. The boy pulls on the rope with a force of 10.0 N; and the sled moves with constant velocity. What is the coefficient of friction between the sled and the ice?

118 A boy pulls a 5.0-kg sled with a rope that makes a 60.0 angle with respect to the horizontal surface of a frozen pond. The boy pulls on the rope with a force of 10.0 N; and the sled moves with constant velocity. What is the coefficient of friction between the sled and the ice?

119 In a tug-of-war, each man on a 5-man team pulls with an average force of 500 N. What is the tension in the center of the rope? 1. zero newtons N N N N

120 In a tug-of-war, each man on a 5-man team pulls with an average force of 500 N. What is the tension in the center of the rope? 1. zero newtons N N N N

121 A 20-kg crate is suspended from a fixed, horizontal beam by two vertical ropes. What is the approximate tension in each rope? N N N N N

122 A 20-kg crate is suspended from a fixed, horizontal beam by two vertical ropes. What is the approximate tension in each rope? N N N N N

123 A woman stands on a bathroom scale in an elevator that is not moving. The scale reads 500 N. The elevator then moves downward at a constant velocity of 5 m/s. What does the scale read while the elevator descends with constant velocity? N N N N N

124 A woman stands on a bathroom scale in an elevator that is not moving. The scale reads 500 N. The elevator then moves downward at a constant velocity of 5 m/s. What does the scale read while the elevator descends with constant velocity? N N N N N

125 A 20.0-kg package is dropped from a high tower in still air and is tracked by a radar system. When the package is 25 m above the ground, the radar tracking indicates that its acceleration is 7.0m/s 2. Determine the force of air resistance on the package N N N N N

126 A 20.0-kg package is dropped from a high tower in still air and is tracked by a radar system. When the package is 25 m above the ground, the radar tracking indicates that its acceleration is 7.0m/s 2. Determine the force of air resistance on the package N N N N N

127 A park ranger wanted to measure the height of a tall tree. The ranger stood 9.50 m from the base of the tree; and he observed that his line of sight made an angle of 65.2 above the horizontal as he looked at the top of the tree. The park ranger s eyes are 1.80 m above the ground. What is the height of the tree? m m m m m

128 A park ranger wanted to measure the height of a tall tree. The ranger stood 9.50 m from the base of the tree; and he observed that his line of sight made an angle of 65.2 above the horizontal as he looked at the top of the tree. The park ranger s eyes are 1.80 m above the ground. What is the height of the tree? m m m m m

129 A physics student standing on the edge of a cliff throws a stone vertically downward with an initial speed of 10.0 m/s. The instant before the stone hits the ground below, it is traveling at a speed of 30.0 m/s. If the physics student were to throw the rock horizontally outward from the cliff instead, with the same initial speed of 10.0 m/s, what is the magnitude of the velocity of the stone just before it hits the ground? m/s m/s m/s 4. The height of the cliff must be specified to answer this question.

130 A physics student standing on the edge of a cliff throws a stone vertically downward with an initial speed of 10.0 m/s. The instant before the stone hits the ground below, it is traveling at a speed of 30.0 m/s. If the physics student were to throw the rock horizontally outward from the cliff instead, with the same initial speed of 10.0 m/s, what is the magnitude of the velocity of the stone just before it hits the ground? m/s m/s m/s 4. The height of the cliff must be specified to answer this question.

131 A tennis ball is thrown from ground level with velocity directed 30 above the horizontal. If it takes the ball 0.5 s to reach the top of its trajectory, what is the magnitude of the initial velocity? m/s m/s m/s m/s m/s

132 A tennis ball is thrown from ground level with velocity directed 30 above the horizontal. If it takes the ball 0.5 s to reach the top of its trajectory, what is the magnitude of the initial velocity? m/s m/s m/s m/s m/s

133 A quarterback throws a pass at an angle of 35 above the horizontal with an initial speed of 25 m/s. The ball is caught by the receiver 2.55 seconds later. Determine the distance the ball was thrown m m m m m

134 A quarterback throws a pass at an angle of 35 above the horizontal with an initial speed of 25 m/s. The ball is caught by the receiver 2.55 seconds later. Determine the distance the ball was thrown m m m m m

135 An arrow is shot horizontally from a height of 4.9 m above the ground. The initial speed of the arrow is 45 m/s. Neglecting friction, how long will it take the arrow to hit the ground? s s s s s

136 An arrow is shot horizontally from a height of 4.9 m above the ground. The initial speed of the arrow is 45 m/s. Neglecting friction, how long will it take the arrow to hit the ground? s s s s s

137 A motorcycle has a velocity of 24 m/s, due south as it passes a car with a velocity of 15 m/s, due north. What is the magnitude and direction of the velocity of the motorcycle as seen by the driver of the car? 1. 9 m/s, north 2. 9 m/s, south m/s, north m/s, north m/s, south

138 A motorcycle has a velocity of 24 m/s, due south as it passes a car with a velocity of 15 m/s, due north. What is the magnitude and direction of the velocity of the motorcycle as seen by the driver of the car? 1. 9 m/s, north 2. 9 m/s, south m/s, north m/s, north m/s, south

139 On a two lane highway, a car is following a pickup truck. At one instant, the car has a speed of 32 m/s and is 184 m behind the truck. At the same time, the truck has a speed of 28 m/s. If neither vehicle accelerates, how long will it take the car to catch up to the truck? s s s s s

140 On a two lane highway, a car is following a pickup truck. At one instant, the car has a speed of 32 m/s and is 184 m behind the truck. At the same time, the truck has a speed of 28 m/s. If neither vehicle accelerates, how long will it take the car to catch up to the truck? s s s s s

141 A basketball player is running at a constant speed of 2.5 m/s when he tosses a basketball upward with a speed of 6.0 m/s. How far does the player run before he catches the ball? Ignore air resistance m m 3. The ball cannot be caught because it will fall behind the player m m

142 A basketball player is running at a constant speed of 2.5 m/s when he tosses a basketball upward with a speed of 6.0 m/s. How far does the player run before he catches the ball? Ignore air resistance m m 3. The ball cannot be caught because it will fall behind the player m m