Chapter #6 Solutions - Physical Science with Modern Applications - Melvin Merken - 5th Edition

 

1. What is the momentum of a 100-kilogram fullback moving at 4.00 m/s? Get solution

2. A heavy body and a light body have the same momentum. Which has the greater velocity? Get solution

3. Is it possible for a body to have energy without having momentum? Get solution

4. Calculate the momentum of a 75.0-kilogram sprinter running with a speed of 12.0 m/s. Get solution

5. A 1500-kilogram automobile travels east with a speed of 8.00 m/s. It slows to a speed of 3.00 m/s in 3.00 s. Find (a) the impulse delivered to the car and (b) the average force exerted on the car during this time. Get solution

6. A 100-gram lump of clay moving eastward at 10.0 m/s collides with a 150-gram lump of clay moving in the same direction at 5.00 m/s. The two coalesce after impact. With what velocity does the combined mass move? Get solution

7. As a tether ball winds around a pole, what happens to its angular velocity? Explain. Get solution

8. A boxer learns to move his head backwards when he sees he is going to receive a jab to the head. What does this head motion accomplish? Get solution

9. What does doubling the speed of a car do to the car’s momentum? Get solution

10. Explain why follow-through is important in hitting a baseball. Get solution

11. Why do gymnasts use padded mats for landings? Get solution

12. As you jump one way from a rowboat, the boat moves in the opposite direction. Explain. Get solution

13. A man pushes a box across the floor by exerting a 10.0-newton force through a distance of 5.00 meters. How much work has he done? Get solution

14. For what quantities are the following units appropriate? (a) kg · m/s; (b) kg · m/s2; (c) kg · m2/s2. Get solution

15. If you push vigorously against a brick wall and it does not move, how much work do you do on the wall? Explain. Get solution

16. How much power does a 70.0-kilogram person develop by running up a 5.00-meter stairway in 10.0 seconds? Get solution

17. A weightlifter 5 ft 2 in tall and another 6 ft 2 in both lift 300 lb. Who does more work? Get solution

18. Two movers raise identical boxes the same vertical distance h. Compare the work done if one lifts the box vertically and the other pushes it up a ramp. Get solution

19. A flight attendant pulls a wheeled suitcase, applying a 60-N force at a 35° angle to the horizontal. How much work does she do in pulling the suitcase 45 m? Get solution

20. A 1500-kg car drives up a mountain road a vertical rise of 1300 m from the base elevation in 30 min. What is the average power output? Get solution

21. A light bulb is rated 100-W. What is its horsepower rating? Get solution

22. An electron is traveling toward the screen of a TV set with a velocity of 2.00 × 106 m/s. If its mass is 9.10 × 10−31 kilograms, what is its kinetic energy? Get solution

23. You roll a bowling ball down the alley. If its mass is 5.00 kilograms and it is moving with a velocity of 6.00 m/s, what is its kinetic energy? Get solution

24. A baseball pitcher throws a 140-gram ball at a speed of 50.0 m/s. How much energy does the catcher absorb when he catches the ball? Get solution

25. An athlete runs the 100-meter dash in 10.0 seconds. What is his kinetic energy while running if his mass is 75.0 kilograms? Get solution

27. A 500-gram mass drops from a height of 10.0 meters. What is its kinetic energy just before it hits the ground? Get solution

29. What does doubling the speed of a car do to the car’s kinetic energy? Get solution

28. A baseball (mass = 0.200 kilogram) is thrown with a speed of 15.0 m/s.(a) What is its KE?(b) If it is thrown at twice this speed, what is its KE? Get solution

30. A helicopter lifts a load of supplies through a vertical distance of 500 meters. What potential energy does the load acquire if its mass is 100 kilograms? Get solution

31. Is it possible for a body to have energy without having momentum? Get solution

32. Explain how a sling shot can have potential energy. Get solution

33. Pulling the bow back farther causes an arrow to have a higher speed when released. Explain. Get solution

34. (a) How do you know that an archery bow has potential energy?(b) What happens to this energy when an arrow is shot? Get solution

35. Does a biker ready to descend at the top of a hill have kinetic or potential energy? Explain. Get solution

36. A 60.0-gram ball is dropped 100 meters from rest.(a) How much potential energy is lost in the fall?(b) What speed does the ball have after it has fallen 100 meters? Get solution

37. Why does a swinging pendulum eventually come to rest? Get solution

38. Is the energy that any mechanical device “wastes” destroyed? Explain. Get solution

39. Explain what “conservation of energy” means in a physical sense. Get solution

40. (a) An apple hanging on a tree has potential energy. Why?(b) When the apple falls, what happens to its potential energy just before it hits the ground? Get solution

41. Sound is considered to be a form of energy. Explain why. Get solution

42. Discuss the energy transformations that occur during the driving of an automobile. Get solution

43. Multiple ChoiceA. Work is(a) energy times distance.(b) force times distance.(c) force times time.(d) momentum times distance.B. You push against Plymouth Rock with a force of 100 newtons for 20.0 seconds. If the rock does not move, how much work have you done?(a) 2000 joules(b) 5.00 joules(c) 1.00 joule(d) 0 jouleC. When an automobile’s speed is doubled, its kinetic energy is(a) twice as large.(b) four times as large.(c) half as large.(d) tripled.D. The rate at which work is done is called(a) momentum.(b) potential energy.(c) kinetic energy.(d) power.E. Energy is(a) lost if heat is produced.(b) a form of power.(c) conserved in a closed system.(d) equal to mv.F. Padded dashboards in automobiles reduce injury by(a) increasing friction.(b) increasing contact time.(c) stopping a person more quickly.(d) conserving momentum.G. When objects stick together after colliding,(a) momentum is not conserved.(b) momentum is zero.(c) the collision is inelastic.(d) the collision is elastic.H. Work is done(a) by any applied force.(b) by all components of force.(c) when a force moves an object.(d) by an applied force perpendicular to the direction of motion.I. When a bird’s speed is doubled, its kinetic energy is(a) half as large.(b) the same.(c) twice as large.(d) four times as large.J. A heavy truck has more momentum than a passenger car moving at the same speed because the truck(a) is not streamlined.(b) has greater mass.(c) has a large wheelbase.(d) has greater velocity. Get solution