Chapter 6 Homework Complete the 11 homework exercises for chapter 6. Answer the problems on your own paper. Question 1 A moving object has a kinetic energy of 180 J, and the magnitude of its momentum is 40.0 kg m/s. Calculate the object's mass and speed. Question 2 A teenager throws a 0.50 kg football at a speed of 18 m/s. His friend, who is stationary, catches the football, bringing it to rest in 0.025 s. Determine: a. the impulse delivered to the ball. b. the average force exerted on the receiver. Question 3 A 725 N man stands in the middle of a frozen round pond that is 12.0 m across. Unable to reach the other side because of the lack of friction between his shoes and the ice, he decides to overcome this difficulty by throwing his 1.9 kg textbook (the mass indicates that it is likely a Phys- ics textbook!) horizontally toward the west shore, at a speed of 6.5 m/s. How long will it take for him to reach the east shore? Question 4 Two friends are engaged in a snowball fight. The first friend, with a mass of 70 kg, throws a fluffy 0.085 kg snowball forward with a speed, relative to the ground, of 35.0 m/s. The second friend, with a mass of 65 kg, catches the snowball. Remarkably, it remains intact. As an added complication, both friends are on ice skates. As the snowball is thrown, the first friend is moving forward with a speed of 2.75 m/s, while the second friend is at rest. Determine the velocities of both people after the snowball is caught. (Disregard any frictional forces between the skates and the ice.) Question 5 A railroad freight car of mass 2.25 104 kg, moving at 3.5 m/s, collides and connects with two coupled freight cars, each of which has the same mass as the single car and is moving in the same direction at 1.25 m/s. a. Calculate the speed of the three-car set after the collision. b. Determine how much kinetic energy is lost in the collision. Question 6 A 20 g object moving to the north at 25 cm/s overtakes and makes a totally elastic collision with a 12 g object that is also moving north at 18 cm/s. Determine the velocity of each object after the collision. Question 7 A marksman fires a 6.7 g bullet into a 3.1 kg ballistic pendulum, where it becomes embedded and causes the pendulum to rise vertically 5.0 cm. What is the initial speed of the bullet? Question 8 A college fullback weighing 100 kg is running north at a speed of 4.5 m/s when he is tackled by a 110 kg linebacker running east at 3.5 m/s. Assume the collision is perfectly inelastic. a. Find the velocity of the players just after the tackle. b. Find the kinetic energy lost as a result of the collision. c. How do you account for this apparently \"lost\" energy? Question 9 Two hockey pucks of equal mass, one blue and one yellow, are involved in a perfectly elastic glancing collision. The yellow puck is initially at rest and is struck by the blue puck, which is moving initially to the right at 6.5 m/s. After the collision, the blue puck moves in a direction that makes an angle of 39 with its initial direction, and the velocity of the yellow puck is perpendicular to that of the blue puck (after the collision). Determine the speed of each puck following the collision. Question 10 An unstable nucleus of mass 18 10-27 kg, which is initially at rest, disintegrates into three particles. One of the particles has a mass of 5.5 10-27 kg and moves along the positive x axis with a speed of 6.5 106 m/s. A second particle has a mass of 8.6 10-27 kg and moves along the positive y axis with a speed of 4.5 106 m/s. What is the third particle's speed and direction of motion? (Hint: Assume that mass is conserved in the disintegration process.) Question 11 A block of wood with a mass of 2.70 kg is placed over the muzzle of a rifle while a bullet of mass 28.0 g is fired vertically upward. The bullet embeds itself in the wood, and the combined mass rises to a maximum height of 3.80 m. Calculate the muzzle velocity of the bullet. Additional Questions Please work any of the problems in the textbook for sections where you are having difficulty. It is important to go through the examples in each chapter and work problems until you are comfortable