Final Review Multiple Choice

f) 25 cm/s

A 5.0-kg mass traveling with velocity 10 cm/s to the right collides head-on with a 2.0-kg mass traveling with velocity v^2 to the left. They stick together in the collision. In order for the stuck-together pair to have zero velocity after the collision, the speed v^2must equal: a) zero b) 6.0 cm/s c) 4.0 cm/s d) 10. cm/s e) 5.0 cm/s f) 25 cm/s

b) 2.4 kg m/s

A 60 g tennis ball travels toward a racket with an initial momentum of -1.2 kg m/s. The force supplied by the racket is shown below as a function of time. If Fmax= 900 N, what is the momentum of the tennis ball as it leaves the net? a) 2.2 kg m/s b) 2.4 kg m/s c) 3.6 kg m/s d) 4.8 kg m/s e) 6.0 kg m/s

d) 10.0 N

A ball is hung from a rope, making a pendulum. When it is pulled 2° to the side, the restoring force is 5.0 N. What will be the magnitude of the restoring force if the ball is pulled 4° to the side? a)2.5 N b)5.0 N c)7.5 N d)10.0 N

b) Velocity is zero, acceleration is negative

A ball is thrown straight up in the air and experiences free fall. At the very top of the ball's path, a) Velocity is zero, acceleration is zero b) Velocity is zero, acceleration is negative c) Velocity is negative, acceleration is zero d) Velocity is negative, acceleration is negative e) Velocity is positive, acceleration is zero f) Velocity is positive, acceleration is negative

a) 7.5 m/s

A bicyclist has the position time graph shown in the figure above. What is the bicyclist's speed at t = 10 s? a) 2.5 m/s b) 7.5 m/s c) 75 m/s d) 750 m/s

b)x = 0

A mass on a spring moves with simple harmonic motion, as shown, and has amplitude A and a period T. Where is the velocity of the mass most positive? a)x = -A b)x = 0 c)x = A

e) 4 m

A one meterlong spring stretches to 2 m when a mass of 3 kg is attached to the end. What is the spring's length when a second 3 kg mass is added to the end? a) 1 m b) 1.5 m c) 2 m d) 3 m e) 4 m

I don't know

An object initially with a kinetic energy of 10 J experiences a net force of 4.0 N as it is moved 2.0 m in in a direction perpendicular to the net force. What is the final kinetic energy of the object after it has been moved 2.0 m? a) zero b) 2 J c) 8 J d) 10 J e) 14 J f) 48 J

588 N

Consider the case where a 588N man hangs from arope connected to a 980 N box that sits on the floor. What is the tension in the rope? a) 392N b) 588N c) 784N d) 980N e) 1568N

c) 3000 rad

Consider the figure above that shows the angular displacement of the blade of a blenderthat has a moment of inertia of 4x 10^-5 kg m^2. Through how many radians does the blade turn in 20 s? a) 1000 rad b) 2000 rad c) 3000 rad d) 4000 rad e) 5000 rad

d) 0.2 J

Consider the figure above that shows the angular displacement of the blade of a blenderthat has a moment of inertia of 4x 10^-5 kg m^2. What is the kinetic energy of the blade at t = 5 s? a) 0.004 J b) 0.008 J c) 0.1 J d) 0.2 J e) 0.4 J

a) 4 x 10-4N m

Consider the figure above that shows the angular displacement of the blade of a blenderthat has a moment of inertia of 4x 10^-5 kg m^2. What is the net torque on the blade at t = 10 s? a) 4 x 10-4N m b) 6x 10-4N m c) 6x 10-3N m d) 1.5x 10-3N m e) 4.5x 10-3N m

c) 1500 J

How much work is done as the object moves from an initial displacement of 5 m to a displacement of 20 m. a) 750 J b) 1000 J c) 1500 J d) 2000 J

b) The elevator speed is increasing as it begins ascending from the 1st to the 5th floor

Standing in an elevator, you give a box sitting on the floor a swift kick to move it across the floor. There is friction between the box and elevator floor. For which case would you have to kick the box the hardest to make it move?a) The elevator speed is increasing as it begins descending from the 5th to 1st floor b) The elevator speed is increasing as it begins ascending from the 1st to the 5th floor c) The elevator is moving upward at a constant speed d) The elevator is moving downward at a constant speed e) The box requires the same level of kick regardless of the elevator motion

b) Graph C

The actual velocity data for a lion pursuing prey are shown in the figure above. What does the acceleration vs. time graph look like? a) Graph A b) Graph B c) Graph C d) Graph D

I don't know

The figure shows data for torque about the knee while walking, where the solid line is the mean and the dashed lines indicate 1 standard deviation. The gait cycle for a human is about 1 second. If the angular momentum about the knee at 0.3 seconds (30% into the gate cycle) is about -7 kg m2/s, estimate the angular momentum about the knee at 0.6 seconds (60%) into the gate cycle. a)-25 kg m^2/s b)-7 kg m^2/s c)-1 kg m^2/s d)4.2 kg m^2/s e)40 kg m^2/s

zero

The velocity vs. time graph for a 1000 kg car is shown above. What is net force on the car when its velocity is zero? a) -8000 N b) zero c) 1000 N d) 2500 N e) 3000 N

I don't know

To particles collide and bounce apart. The figure above shows the initial momentum both and the final momentum of particle 2. Which vectorshows the final momentum a particle 1?

e) 1200 N

When you stand on your tiptoes, your feet pivot about your ankle. As shown in the figure, the forces on your foot are an upward force on your toes from the floor, a downward force on your ankle from the lower leg bone, and an upward force on the heel of your foot from your Achilles tendon. Suppose a 800 N man stands on tiptoes with the sole of his foot making a 30 degree angle with the floor. Assume that the normal force on each foot supports half his weight. What upward force does the Achilles tendon exert on the heel of his foot? a)200 N b)400 N c)900 N d)1000 N e)1200 N

b) The frictional force of the road on the car's tires and the frictional force of the car's tires on the road.

Newton's third law is concerned with action-reaction pairs. Consider a car accelerating along a highway. Which of the following is an appropriate pair of forces showing Newton's third law? a) The weight of the car pulling it downand the normal force of the road pushing it up. b) The frictional force of the road on the car's tires and the frictional force of the car's tires on the road. c) The engine's force making the car go forward and the car's brakes making it go backwards. d)The engine's force making the car go forward and the car's acceleration.

a) Increases

Relative to the ground, an airplane gains speed when it encounters wind from behind, and loses speed when it encounters wind head on. When it encounters wind at a right angle to the direction it is pointing, its speed relative to the ground below a) Increases b) Decreases c) Is the same as if there were no wind