PhysicsLAB: Practice: Momentum and Energy #2

Refer to the following information for the next four questions.

In a ballistics lab, a 10-gram bullet is shot into a 2-kg block of wood suspended by a 1-meter rope from the ceiling. During the collision, the bullet is embedded in the block. After the collision, the block-bullet swing up 53º. You may use g = 10 m/sec².

How much potential energy does the block-bullet have when they reach 53º?

How fast was the block-bullet traveling after the collision?

How fast was the bullet originally traveling before it collided with the block?

What percent of the bullet's original KE was lost during this collision?

Refer to the following information for the next six questions.

A neutron (m = 1.67 x 10^-27 kg) moving with speed 1 m/sec, collides with a stationary particle of unknown mass. The neutron undergoes a perfectly elastic collision and rebounds with a speed of 0.85 m/sec.

What is the neutron's initial KE?

What is the neutron's final KE?

Since the collision is perfectly elastic, how much KE must the second particle acquire during the collision?

What is the neutron's change in momentum?

How much momentum does the second particle acquire during the collision?

What is the mass of the second particle?

Refer to the following information for the next four questions.

A 20-gram bullet is fired at a 3500-gram block which is initially at rest on a table. The bullet embeds in the block resulting in the block sliding 1.75 meters before coming to a stop. The coefficient of friction between the block and the table's surface is µ = 0.40. You may g = 10 m/sec².

How much friction is present between the two surfaces?

How much kinetic energy was lost as the block was brought to a stop?

How fast will the bullet-block sliding across the table immediately after the collision?

How fast was the bullet originally traveling before it struck the block?

Refer to the following information for the next eleven questions.

As shown in the diagrams provided below, a ball of mass 1 kg is originally moving along the x-axis with a velocity of 10 m/sec towards the origin. As it approaches the origin, it delivers a glancing blow to a stationary 4-kg mass. After the collision, the 1-kg ball continues traveling towards the left, into the second quadrant, at a reduced speed of 5 m/sec at an angle of 37º above the negative x-axis.

Calculate the total x-momentum present in the two-ball system before the collision.

Calculate the total y-momentum present in the two-ball system before the collision.

After the collision, calculate the x-momentum of the 1-kg ball.

Calculate the 1-kg ball's y-momentum after the collision.

Using conservation of momentum techniques, what should be the x-momentum of the 4-kg ball after the collision?

Using conservation of momentum techniques, what should be the y-momentum of the 4-kg ball after the collision?

Calculate the magnitude of the 4-kg ball's resultant velocity after the collision.

Calculate the angle that the 4-kg ball's trajectory makes with the negative x-axis.

Calculate the total KE before the collision.

Calculate the total KE after the collision.

Was this collision elastic or inelastic?