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 = 17 N and F_min = -12 N then calculate the impulse delivered to a 4-kg mass during the 5 seconds graphed above.
-13 N sec-2 N sec35 N sec47 N sec-1 N sec

		Question 2 If the object's initial velocity in Question 1 was 7.5 m/sec, what will be its final velocity at the end of these 5 seconds?
7.2 m/sec29 m/sec1.6 m/sec-7.8 m/sec4.2 m/sec

		Question 3 What was the magnitude of the average force acting on the 4-kg mass in Question 1 during the 5 seconds displayed on the graph?
2.5 N-5 N-0.2 N7 N-2.6 N

		Question 4 A 7.5-gram bullet moving at 300 m/sec travels through a block of wood and emerges out the other side moving at 200 m/sec. If it takes 28.3 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?
7.95 x 10⁴ N-2.65 x 10⁴ N1.33 x 10⁶ N5.3 x 10⁴ N

		Question 5 During target practice, a man shoots a 7.5-gram bullet with a horizontal velocity of 200 m/sec at a 2-kg wooden block balanced on the top of a 1.2-meter tall fence post. If the bullet embeds in the block, how fast will the block-bullet be knocked off the post?
199.25 m/sec100 m/sec0.075 m/sec0.75 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?
0.37 m0.99 m0.18 m0.7 m0.26 m

		Question 7 A second 7.5-gram bullet is fired at another 2-kg block which is initially at rest on a table. The bullet embeds in the block resulting in the block sliding 158 centimeters before coming to a stop. The coefficient of friction between the block and the table's surface is µ = 0.372. How much work will the friction between the table and block do on the block while bringing it to a stop?
58.8 J7.3 J11.6 J4.6 J31.1 J

		Question 8 How fast was the original bullet in Question 7 travelling before it struck the block?
909.9 m/sec430.6 m/sec340 m/sec580 m/sec249.9 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 12 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?

8 kg m/sec3 kg m/sec8.5 kg m/sec17 kg m/sec6 kg m/sec

		Question 10 Within the system, what fraction of the 1-kg ball's original KE remains after the collision?
0.180.7710.4240.5940.266