A ladder is resting with one end on a vertical wall and the other end on the ground. Which of the following contact forces can be zero while still keeping the ladder in equilibrium? A. Normal force exerted by the ground on the ladder B. Normal force exerted by the wall on the ladder C. Frictional force exerted by the wall on the ladder D. Frictional force exerted by the ground on the ladder

A ladder is resting with one end on a vertical wall and the other end on the ground. Which of the following contact forces can be zero while still keeping the ladder in equilibrium? A. Normal force exerted by the ground on the ladder B. Normal force exerted by the wall on the ladder C. Frictional force exerted by the wall on the ladder D. Frictional force exerted by the ground on the ladder

Principles of Physics: A Calculus-Based Text

5th Edition

ISBN:9781133104261

Author:Raymond A. Serway, John W. Jewett

Publisher:Raymond A. Serway, John W. Jewett

Chapter10: Rotational Motion

Section: Chapter Questions

Problem 17CQ

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A massless, horizontal beam of length L and a massless rope support a sign of mass m (Fig. P14.78). a. What is the tension in the rope? b. In terms of m, g, d, L, and , what are the components of the force exerted by the beam on the wall? FIGURE P14.78
(a) Give an example in which the net force acting on an object is zero, yet the net torque is nonzero, (b) Give an example in which the net torque acting on an object is zero, yet the net force is nonzero.
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Unreasonable Results Suppose two children are using a uniform seesaw that is 3.00 m long and has its center of mass over the pivot. The first child has a mass of 30.0 kg and sits 1.40 m from the pivot. (a) Calculate where the second 18.0 kg child must sit to balance the seesaw. (b) What is unreasonable about the result? (c) Which premise is unreasonable, or which premises are inconsistent?
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