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 = -11 N then calculate the impulse delivered to a 3-kg mass during the 5 seconds graphed above.
46.5 N sec-8.5 N sec35.5 N sec2.5 N sec5 N sec

		Question 2 If the object's initial velocity in Question 1 was 6.9 m/sec, what will be its final velocity at the end of these 5 seconds?
4.1 m/sec7.7 m/sec3.1 m/sec-6.1 m/sec23.2 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?
4 N7.1 N12.5 N-1.7 N0.5 N

		Question 4 A 6.9-gram bullet moving at 260 m/sec travels through a block of wood and emerges out the other side moving at 230 m/sec. If it takes 27.5 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?
6.52 x 10⁴ N5.77 x 10⁴ N-7.53 x 10³ N1.23 x 10⁶ N

		Question 5 During target practice, a man shoots a 6.9-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?
0.045 m/sec153.33 m/sec1.05 m/sec228.95 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?
0.5 m1.08 m0.35 m0.24 m0.77 m

		Question 7 A second 6.9-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 174 centimeters before coming to a stop. The coefficient of friction between the block and the table's surface is µ = 0.369. How much work will the friction between the table and block do on the block while bringing it to a stop?
9.5 J64.2 J5.4 J3.1 J25.7 J

		Question 8 How fast was the original bullet in Question 7 travelling before it struck the block?
355.1 m/sec775.5 m/sec432.3 m/sec240.1 m/sec475 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/sec7 kg m/sec5.5 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?
0.1980.3120.4450.640.8