Author Question: An instructor fires an arrow into a wooden block suspended by strings, as shown. If the mass of the ... (Read 54 times)

Haya94 · **on:** Jul 28, 2018

An instructor fires an arrow into a wooden block suspended by strings, as shown. If the mass of the arrow is 1/10 the mass of the block, what is the momentum of the arrow relative to the momentum of the block after the arrow has fully penetrated the block and is moving with it?
a. The same.
b. The momentum of the arrow is 1/10 that of the block.
c. The momentum of the arrow is ten times that of the block.
d. The momentum of the arrow is 100 times that of the block because the kinetic energy is mv2.
e. The momentum of the arrow is 1/100 times that of the block because the kinetic energy is mv2.

Question 2

When you walk forward on a scooter that was previously at rest, how do you calculate the total momentum of you and the scooter?
a. You don't have to calculate it; you already know that it is zero.
b. You measure how far you move forward and how far the scooter moves backward, and average the two.
c. You measure how far you move forward and how far the scooter moves forward, and add the two.
d. You calculate the forces on the scooter in newtons by adding mass and acceleration.
e. You calculate the forces on the scooter in newtons by multiplying mass and acceleration.