The figure shows three forces applied to a trunk that moves leftward by 2.63 m over a frictionless floor. The force magnitudes are F1 = 5.16 N, F2 = 8.74 N, and F3 = 3.23 N, and the indicated angle is 0 = 60°. (a) During the displacement, what is the net work done on the trunk by the three applied forces, the gravitational force, and the normal force? (b) Is there a net transfer of energy to or from the trunk? (c) Does the cinetic energy of the trunk increase or decrease?

The figure shows three forces applied to a trunk that moves leftward by 2.63 m over a frictionless floor. The force magnitudes are F1 = 5.16 N, F2 = 8.74 N, and F3 = 3.23 N, and the indicated angle is 0 = 60°. (a) During the displacement, what is the net work done on the trunk by the three applied forces, the gravitational force, and the normal force? (b) Is there a net transfer of energy to or from the trunk? (c) Does the cinetic energy of the trunk increase or decrease?

International Edition---engineering Mechanics: Statics, 4th Edition

4th Edition

ISBN:9781305501607

Author:Andrew Pytel And Jaan Kiusalaas

Publisher:Andrew Pytel And Jaan Kiusalaas

Chapter7: Dry Friction

Section: Chapter Questions

Problem 7.78P: The figure shows a steel bar being processed by a rolling mill. Given that P=80kN and r =0.016,...

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