Conceptual Physics (12th Edition)
12th Edition
ISBN: 9780321909107
Author: Paul G. Hewitt
Publisher: PEARSON
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Chapter 8, Problem 13RCQ
To determine
What is “lever arm” of a torque?
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A uniform ladder of length L and weight w is leaning against a vertical wall. The coefficient of static friction between the ladder and the floor is the same as that between the ladder and the wall. If this
coefficient of static friction is μs : 0.535, determine the smallest angle the ladder can make with the floor without slipping.
°
=
A 14.0 m uniform ladder weighing 480 N rests against a frictionless wall. The ladder makes a 55.0°-angle with the horizontal.
(a) Find the horizontal and vertical forces (in N) the ground exerts on the base of the ladder when an 850-N firefighter has climbed 4.10 m along the ladder from the bottom.
horizontal force
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342.
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vertical force
1330
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(b) If the ladder is just on the verge of slipping when the firefighter is 9.10 m from the bottom, what is the coefficient of static friction between ladder and ground?
0.26
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You appear to be using 4.10 m from part (a) for the position of the…
Your neighbor designs automobiles for a living. You are fascinated with her work. She is designing a new automobile and needs to determine how strong the front suspension should be. She knows of
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ma
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hcm = 0.630 m above the roadway. A typical coefficient of kinetic friction between tires and roadway is μk 0.840. (Caution: The braking automobile is not in an inertial reference frame. Enter the
magnitude of the force in N.)…
John is pushing his daughter Rachel in a wheelbarrow when it is stopped by a brick 8.00 cm high (see the figure below). The handles make an angle of 0 = 17.5° with the ground. Due to the weight of
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magnitude (No Response) KN
direction
(No Response) ° clockwise from the -x-axis
Chapter 8 Solutions
Conceptual Physics (12th Edition)
Ch. 8 - What are the units of measurement for tangential...Ch. 8 - On a rotating turntable, does tangential speed or...Ch. 8 - A tapered cup rolled on a flat surface makes a...Ch. 8 - How does the tapered rim of a wheel on a railroad...Ch. 8 - 5. What is rotational inertia, and how is it...Ch. 8 - 6. Inertia depends on mass; rotational inertia...Ch. 8 - 7. As distance increases between most of the mass...Ch. 8 - 8. Consider three axes of rotation for a pencil:...Ch. 8 - 9. Which is easier to get swinging: a baseball bat...Ch. 8 - Why does bending your legs when running enable you...
Ch. 8 - 11. Which will have the greater acceleration...Ch. 8 - 12. What does a torque tend to do to an object?
Ch. 8 - 13. What is meant by the “lever arm” of a...Ch. 8 - 14. How do clockwise and counterclockwise torques...Ch. 8 - 15. If you toss a stick into the air, it appears...Ch. 8 - Prob. 16RCQCh. 8 - 17. If you hang at rest by your hands from a...Ch. 8 - Where is the center of mass of a hollow soccer...Ch. 8 - 19. What is the relationship between the center of...Ch. 8 - 20. Why doesn’t the Leaning Tower of Pisa topple...Ch. 8 - 21. In terms of center of gravity, support base,...Ch. 8 - 22.When you whirl a can at the end of a string in...Ch. 8 - 23. Is it an inward force or an outward force that...Ch. 8 - 24. If the string that holds a whirling can in its...Ch. 8 - 25. If you are not wearing a seat belt in a car...Ch. 8 - 26. Why is centrifugal force in a rotating frame...Ch. 8 - 27. How can gravity be simulated in an orbiting...Ch. 8 - 28. Distinguish between linear momentum and...Ch. 8 - 29. What is the law of inertia for rotating...Ch. 8 - If a skater who is spinning pulls her arms in so...Ch. 8 - Contact Grandpa and tell him how you’re learning...Ch. 8 - Prob. 32RCQCh. 8 - Prob. 33RCQCh. 8 - Prob. 34RCQCh. 8 - Prob. 35RCQCh. 8 - Prob. 36RCQCh. 8 - Prob. 37RCQCh. 8 - Torque = lever arm ×...Ch. 8 - 39. Calculate the torque produced by the same 50-N...Ch. 8 - Prob. 40RCQCh. 8 - 41. Calculate the force of friction that keeps an...Ch. 8 - Angular momentum =...Ch. 8 - 43. If a persons speed doubles and all else...Ch. 8 - 44. The diameter of the base of a tapered...Ch. 8 - To tighten a bolt, you push with a force of 80 N...Ch. 8 - 46. The rock and meterstick balance at the 25-cm...Ch. 8 - In one of the photos at the beginning of this...Ch. 8 - 48. An ice puck of mass m revolves on an icy...Ch. 8 - 49. If a trapeze artist rotates once each second...Ch. 8 - A small space telescope at the end of a tether...Ch. 8 - 51. The three cups are rolled on a level surface....Ch. 8 - 52. Three types of rollers are placed on slightly...Ch. 8 - 53. Beginning from a rest position, a solid disk...Ch. 8 - 54. You hold a meterstick at one end with the same...Ch. 8 - 55. Three physics majors in good physical shape...Ch. 8 - Prob. 56RCQCh. 8 - Prob. 57RCQCh. 8 - Prob. 58RCQCh. 8 - 59. The wheels of railroad trains are tapered, a...Ch. 8 - Prob. 60RCQCh. 8 - 61. The front wheels of a racing vehicle are...Ch. 8 - 62. Which will have the greater acceleration...Ch. 8 - Prob. 63RCQCh. 8 - 64. Is the net torque changed when a partner on a...Ch. 8 - Prob. 65RCQCh. 8 - 66. When you pedal a bicycle, maximum torque is...Ch. 8 - Prob. 67RCQCh. 8 - Prob. 68RCQCh. 8 - Prob. 69RCQCh. 8 - Prob. 70RCQCh. 8 - 71. Explain why a long pole is more beneficial to...Ch. 8 - Prob. 72RCQCh. 8 - Prob. 73RCQCh. 8 - Prob. 74RCQCh. 8 - Prob. 75RCQCh. 8 - Prob. 76RCQCh. 8 - Prob. 77RCQCh. 8 - Prob. 78RCQCh. 8 - 79. The centers of gravity of the three trucks...Ch. 8 - Prob. 80RCQCh. 8 - Prob. 81RCQCh. 8 - Prob. 82RCQCh. 8 - 83. When you are in the front passenger seat of a...Ch. 8 - Prob. 84RCQCh. 8 - Prob. 85RCQCh. 8 - Prob. 86RCQCh. 8 - 87. The occupant inside a rotating space habitat...Ch. 8 - Prob. 88RCQCh. 8 - A motorcyclist is able to ride on the vertical...Ch. 8 - 90. The sketch shows a conical pendulum. The bob...Ch. 8 - Prob. 91RCQCh. 8 - Prob. 92RCQCh. 8 - Prob. 93RCQCh. 8 - 94. If all of Earth’s inhabitants moved to the...Ch. 8 - Prob. 95RCQCh. 8 - If the world’s populations moved to the North Pole...Ch. 8 - Prob. 97RCQCh. 8 - 98. Why does a typical small helicopter with a...Ch. 8 - 99. We believe that our galaxy was formed from a...Ch. 8 - Prob. 100RCQCh. 8 - Prob. 101RCQCh. 8 - Prob. 102RCQCh. 8 - Prob. 103RCQCh. 8 - 104.When a car drives off a cliff it rotates...Ch. 8 - 105. Discuss why a car noses up when accelerating...Ch. 8 - 106. Discuss how a ramp would help you to...Ch. 8 - 107. Which will roll down an incline faster: a can...Ch. 8 - 108. Why are lightweight tires preferred in...Ch. 8 - 109. A youngster who has entered a soapbox derby...Ch. 8 - 110. The spool is pulled in three ways, as shown....Ch. 8 - 111. Nobody at the playground wants to play with...Ch. 8 - 112. How can the three bricks be stacked so that...Ch. 8 - 113. A long track balanced like a seesaw supports...Ch. 8 - With respect to Diana’s finger, where is the...Ch. 8 - When a long-range cannonball is fired toward the...Ch. 8 - Most often we say that force causes acceleration....
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