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 = 19 N and F_min = -14 N then calculate the impulse delivered to a 3-kg mass during the 5 seconds graphed above.
-2 N sec40 N sec-4 N sec-16 N sec54 N sec

		Question 2 If the object's initial velocity in Question 1 was 6.4 m/sec, what will be its final velocity at the end of these 5 seconds?
17.2 m/sec5.7 m/sec1.1 m/sec-7.1 m/sec1.5 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?
-3.2 N2.5 N-0.4 N8 N-10 N

		Question 4 A 6.4-gram bullet moving at 270 m/sec travels through a block of wood and emerges out the other side moving at 230 m/sec. If it takes 27.9 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?
5.28 x 10⁴ N6.19 x 10⁴ N-9.18 x 10³ N1.15 x 10⁶ N

		Question 5 During target practice, a man shoots a 6.4-gram bullet with a horizontal velocity of 230 m/sec at a 1.5-kg wooden block balanced on the top of a 1.4-meter tall fence post. If the bullet embeds in the block, how fast will the block-bullet be knocked off the post?
0.98 m/sec229.02 m/sec0.042 m/sec153.33 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?
0.87 m0.28 m1.22 m0.52 m0.37 m

		Question 7 A second 6.4-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 = 0.373. How much work will the friction between the table and block do on the block while bringing it to a stop?
3.1 J66 J9.7 J26.1 J5.5 J

		Question 8 How fast was the original bullet in Question 7 travelling before it struck the block?
443 m/sec358.9 m/sec485 m/sec225.1 m/sec844.7 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 14 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?

3 kg m/sec7 kg m/sec10.4 kg m/sec10 kg m/sec20.8 kg m/sec

		Question 10 Within the system, what fraction of the 1-kg ball's original KE remains after the collision?
0.4030.5310.210.7290.162