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 = 15 N and F_min = -12 N then calculate the impulse delivered to a 3-kg mass during the 5 seconds graphed above.
-15 N sec-3 N sec33 N sec-6 N sec45 N sec

		Question 2 If the object's initial velocity in Question 1 was 7.2 m/sec, what will be its final velocity at the end of these 5 seconds?
6.2 m/sec1.4 m/sec18.6 m/sec2.2 m/sec-8.2 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?
-15 N-0.6 N-3 N1.5 N6.6 N

		Question 4 A 7.2-gram bullet moving at 260 m/sec travels through a block of wood and emerges out the other side moving at 240 m/sec. If it takes 28.6 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?
-5.04 x 10³ N6.55 x 10⁴ N6.04 x 10⁴ N1.26 x 10⁶ N

		Question 5 During target practice, a man shoots a 7.2-gram bullet with a horizontal velocity of 240 m/sec at a 1.5-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?
238.85 m/sec0.045 m/sec160 m/sec1.15 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?
1.18 m0.57 m0.4 m0.84 m0.28 m

		Question 7 A second 7.2-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 177 centimeters before coming to a stop. The coefficient of friction between the block and the table's surface is µ = 0.388. How much work will the friction between the table and block do on the block while bringing it to a stop?
10.1 J3.2 J5.7 J26.1 J68.7 J

		Question 8 How fast was the original bullet in Question 7 travelling before it struck the block?
366.1 m/sec258.3 m/sec766.4 m/sec442.4 m/sec505 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/sec6 kg m/sec8.5 kg m/sec17 kg m/sec

		Question 10 Within the system, what fraction of the 1-kg ball's original KE remains after the collision?
0.180.4240.2660.7710.594