Momentum and Energy

Practice Problems
Momentum and Energy

Directions: On this worksheet you will be investigating the relationships between momentum and energy.

		Question 1 If F_max = 18 N and F_min = -11 N then calculate the impulse delivered to a 3-kg mass during the 5 seconds graphed above.
45.5 N sec34.5 N sec3 N sec-9.5 N sec1.5 N sec

		Question 2 If the object's initial velocity in Question 1 was 8.9 m/sec, what will be its final velocity at the end of these 5 seconds?
28.2 m/sec5.7 m/sec3.5 m/sec-8.4 m/sec9.4 m/sec

		Question 3 What was the magnitude of the average force acting on the 3-kg mass in Question 1 during the 5 seconds displayed on the graph?
-1.9 N3.5 N6.9 N7.5 N0.3 N

		Question 4 A 8.9-gram bullet moving at 250 m/sec travels through a block of wood and emerges out the other side moving at 230 m/sec. If it takes 29.9 µsecs (1 µsec = 1 x 10^-6 seconds) for the bullet to bore through the wood, what average force did the wood exert on the bullet?
6.85 x 10⁴ N-5.95 x 10³ N7.44 x 10⁴ N1.43 x 10⁶ N

		Question 5 During target practice, a man shoots a 8.9-gram bullet with a horizontal velocity of 230 m/sec at a 1.5-kg wooden block balanced on the top of a 1.1-meter tall fence post. If the bullet embeds in the block, how fast will the block-bullet be knocked off the post?
1.36 m/sec228.64 m/sec153.33 m/sec0.058 m/sec

		Question 6 After being knocked off, how far from the base of the fence post will the block in Question 5 hit the ground?
0.77 m0.31 m1.08 m0.64 m0.46 m

		Question 7 A second 8.9-gram bullet is fired at another 1.5-kg block which is initially at rest on a table. The bullet embeds in the block resulting in the block sliding 165 centimeters before coming to a stop. The coefficient of friction between the block and the table's surface is µ = 0.374. How much work will the friction between the table and block do on the block while bringing it to a stop?
5.5 J61.7 J24.4 J9.1 J3.4 J

		Question 8 How fast was the original bullet in Question 7 travelling before it struck the block?
405.8 m/sec347.3 m/sec302.9 m/sec455 m/sec588.8 m/sec

Question 9 As shown in the diagrams provided below, a ball of mass 1 kg is originally moving along the x-axis with a velocity of 11 m/sec towards the origin. As it approaches the origin, it delivers a glancing blow to a stationary 2-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.

What is the final momentum of the 2-kg mass after the collision?

7.6 kg m/sec5.5 kg m/sec7 kg m/sec3 kg m/sec15.2 kg m/sec

		Question 10 Within the system, what fraction of the 1-kg ball's original KE remains after the collision?
0.80.3120.4450.1980.64