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 = 16 N and F_min = -13 N then calculate the impulse delivered to a 4-kg mass during the 5 seconds graphed above.
-3.5 N sec48.5 N sec-16.5 N sec-7 N sec35.5 N sec

		Question 2 If the object's initial velocity in Question 1 was 6.1 m/sec, what will be its final velocity at the end of these 5 seconds?
2 m/sec-7 m/sec0.6 m/sec5.2 m/sec20.9 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?
1.5 N-0.7 N7.1 N-3.3 N-17.5 N

		Question 4 A 6.1-gram bullet moving at 280 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?
1.12 x 10⁶ N5.03 x 10⁴ N-1.09 x 10⁴ N6.12 x 10⁴ N

		Question 5 During target practice, a man shoots a 6.1-gram bullet with a horizontal velocity of 230 m/sec at a 2-kg wooden block balanced on the top of a 1.3-meter tall fence post. If the bullet embeds in the block, how fast will the block-bullet be knocked off the post?
115 m/sec229.3 m/sec0.7 m/sec0.053 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?
0.84 m0.36 m1.18 m0.25 m0.19 m

		Question 7 A second 6.1-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 162 centimeters before coming to a stop. The coefficient of friction between the block and the table's surface is µ = 0.396. How much work will the friction between the table and block do on the block while bringing it to a stop?
12.6 J31.8 J7.8 J4.8 J64.2 J

		Question 8 How fast was the original bullet in Question 7 travelling before it struck the block?
470.6 m/sec211.9 m/sec1165.6 m/sec630 m/sec354.4 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 13 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?

6.5 kg m/sec9.5 kg m/sec9 kg m/sec19 kg m/sec3 kg m/sec

		Question 10 Within the system, what fraction of the 1-kg ball's original KE remains after the collision?
0.4150.1720.750.2440.562