If you jump to the floor from the top of a table, it is less hurtful when you bend your
knees as you hit the ground (as compared to if you keep them straight and rigid),
because:
a- There is less change in momentum in the fall.
b- The impulse is reduced.
c- The landing, and thus the change in momentum, takes longer.

A 5.00 kg object is moving to the right at 5.00 m/s and collides with a 2.00 kg object
moving to the left at 2.00 m/s. The objects collide and stick together and move to the
right at 3 m/s. This collision is a case of:
a. Elastic Collision.
b. In-Elastic Collision.
c. Perfectly In-Elastic Collision.
d. Multi-step collision

If you throw a ball and it hits a wall with a speed V, in which case will the change in
momentum of the ball be greatest:
a- When the ball bounces back with a speed = V/2.
b- When it bounces back with speed = V.
c- When it sticks to the wall (does not bounce back).

When a gun is fired, it experiences a recoil which is explained on the basis of:
a- Conservation of kinetic energy.
b- Conservation of sum of kinetic and potential energy.
c- Conservation of Momentum.
d- Conservation of mass.

In a Perfectly In-Elastic Collision between two objects:
a- The two objects stick and move off together.
b- Momentum of the two objects is not conserved.
c- The two objects reverse their directions after the collision.
d- Sum of the Kinetic energy of the two objects is conserved

When a gun fires a bullet, the gun will recoil backward. The magnitude of the
momentum of the gun will be __________ that of the bullet.
a- Greater than
b- Equal to
c- Less than

A 5-kg object is moving to the right at 4 m/s and collides with another object of unknown mass moving to the left at 4 m/s. The objects collide and stick together. After the collision, which one of the following statements will always be true about the combined object?
Group of answer choices

it has less kinetic energy than the system had before the collision.

it has less momentum than the system had before the collision.

is moving to the left.

is at rest.

is moving to the right.

Flag question: Question 2
Question 21 pts
A 70-kg man is standing in a 20-kg boat. The man steps to the right thinking he is stepping out onto the dock. However, the following will actually happen (ignore the friction of the water or air on the boat or the man):
Group of answer choices

The man only moves a short distance to the right while the boat moves a larger distance to the left.

None of the above.

The boat doesn't move and the man moves to the right.

The man actually stays still while the boat moves toward the left.

Flag question: Question 3
Question 31 pts
A moderate force will break an egg. However, an egg dropped on the road usually breaks, while one dropped on the grass usually doesn't break. This is because for the egg dropped on the grass:
Group of answer choices

the time interval for stopping is greater.

the change in momentum is greater.

the time interval for stopping is less.

the change in momentum is less.

Flag question: Question 4
Question 41 pts
A valid unit for momentum is which of the following?
Group of answer choices

N×m

kg/m²

kg×m/s

kg×m/s²

Flag question: Question 5
Question 51 pts
In a two-body collision, if the kinetic energy of the system is conserved, then which of the following best describes the momentum after the collision?
Group of answer choices

is doubled in value

must be less

must also be conserved

may also be conserved

Flag question: Question 6
Question 61 pts
The impulse experienced by a body is equivalent to its change in:
Group of answer choices

momentum.

velocity.

None of the above choices are valid.

kinetic energy.

Flag question: Question 7
Question 71 pts
In a two-body collision, the momentum of the system is always conserved. Which of the following best describes the kinetic energy after the collision?
Group of answer choices

may or may not be conserved

must also be conserved

is doubled in value

must be less

Flag question: Question 8
Question 81 pts
When a collision is perfectly inelastic, then:
Group of answer choices

the total momentum is zero.

the participants stick together.

all the kinetic energy is conserved.

all the kinetic energy is gone.

A bullet of mass 30.0 gram is fired vertically upwards at a speed of 100 m/s. What will be its kinetic energy when it is at a height of 30.0 meters?

A car crashes into a solid wall. The mass of the car is 1000 kg, its speed before the
collision was 20.0 m/s, and the car stops in a time 0.100 s (i.e. the collision takes 0.100s). What is the average value of the magnitude of the force on the car during the
collision?

A 40-g bullet moving at 400 m/s is fired horizontally at a block of wood of mass 800 grams. It gets lodges inside the block. If the block had been originally at rest and is free to move, what is its resulting speed of the block+bullet? Ignore friction.