Problem 5 A child applies a force F? parallel to the x-axis to a 10.0-kg sled moving on the frozen surface of a small pond. As the child controls the speed of the sled, the x-component of the force she applies varies with the x-coordinate of the sled as shown in the picture (a) Calculate the work done by the force F? when the sled moves from x=0 to x-8.0m. (b) from x = 8.0 m to x = 12.0 m; (c) from x = 0 to 12.0 m. Figure 1 F, (N) 10 5 of 1 0 4 8 < 12 x (m)

Problem 5 A child applies a force F? parallel to the x-axis to a 10.0-kg sled moving on the frozen surface of a small pond. As the child controls the speed of the sled, the x-component of the force she applies varies with the x-coordinate of the sled as shown in the picture (a) Calculate the work done by the force F? when the sled moves from x=0 to x-8.0m. (b) from x = 8.0 m to x = 12.0 m; (c) from x = 0 to 12.0 m. Figure 1 F, (N) 10 5 of 1 0 4 8 < 12 x (m)

Name: Problem 5A child applies a force F? parallel to the x -axis to a 10.0
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Description: Problem 5A child applies a force F? parallel to the x -axis to a 10.0-kg sled moving on the frozen surface ofa small pond. As the child controls the speed of the sled, the x-component of the force sheapplies varies with the x-coordinate of the sled

Physics for Scientists and Engineers with Modern Physics

10th Edition

ISBN:9781337553292

Author:Raymond A. Serway, John W. Jewett

Publisher:Raymond A. Serway, John W. Jewett

Chapter7: Energy Of A System

Section: Chapter Questions

Problem 9P: A particle is subject to a force Fx that varies with position as shown in Figure P7.9. Find the work...

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a shopper in a supermarket pushes a cart with a force of 35 N directed at an angle of 25 below the horizontal. The force is just sufficient to overcome various frictional forces, so the cart moves at constant speed, (a) Find the work done by the shopper as she moves down a 50.0-m length aisle, (b) What is the net work done on the cart? Why? (c) The shopper goes down the next aisle, pushing horizontally and maintaining the same speed as before. If the work done by frictional forces doesnt change, would the shoppers applied force be larger, smaller, or the same? What about the work done on the cart by the shopper?
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As a simple pendulum swings back and forth, the forces acting on the suspended object are the force of gravity, the tension in the supporting cord, and air resistance, (a) Which of these forces, if any, does no work on the pendulum? (b) Which of these forces does negative work at all times during the pendulums motion? (c) Describe the work done by the force of gravity while the pendulum is swinging.
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