An Atwood machine consists of two masses connected by a cable wrapped over a pulley. M1 = 75.0 kg and M2 = 30.0 kg. The system is released from rest. Neglect friction and the mass of the cable. a) Use the conservation of mechanical energy to determine the acceleration of the masses after they have moved 2.0 m. b) Does this pulley offer a mechanical advantage? Briefly explain. c) Eventually the cable breaks and M1 falls onto a spring directly below it. The spring compresses 5.5 cm. What is the spring constant of this spring? 2

An Atwood machine consists of two masses connected by a cable wrapped over a pulley. M1 = 75.0 kg and M2 = 30.0 kg. The system is released from rest. Neglect friction and the mass of the cable. a) Use the conservation of mechanical energy to determine the acceleration of the masses after they have moved 2.0 m. b) Does this pulley offer a mechanical advantage? Briefly explain. c) Eventually the cable breaks and M1 falls onto a spring directly below it. The spring compresses 5.5 cm. What is the spring constant of this spring? 2

College Physics

11th Edition

ISBN:9781305952300

Author:Raymond A. Serway, Chris Vuille

Publisher:Raymond A. Serway, Chris Vuille

Chapter5: Energy

Section: Chapter Questions

Problem 39P: The launching mechanism of a toy gun consists of a spring of unknown spring constant, as shown in...

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The launching mechanism of a toy gun consists of a spring of unknown spring constant, as shown in Figure P5.39a. If the spring is compressed a distance of 0.120 m and the gun fired vertically as shown, the gun can launch a 20.0-g projectile from rest to a maximum height of 20.0 m above the starting point of the projectile. Neglecting all resistive forces, (a) describe the mechanical energy transformations that occur from the time the gun is fired until the projectile reaches its maximum height, (b) determine the spring constant, and (c) find the speed of the projectile as it moves through the equilibrium position of the spring (where x = 0), as shown in Figure P5.39b. Figure P5.39
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