*64. GO A block is pressed against a vertical wall by a force P, as the drawing shows. This force can either push the block upward at a constant ve- locity or allow it to slide downward at a constant velocity. The magnitude of the force is different in the two cases, while the directional angle 0 is the same. Kinetic friction exists between the block and the wall, and the coefficient of kinetic friction is 0.250. The weight of the block is 39.0 N, and the directional angle for the force P is 0 = 30.0°. Determine the magnitude of P when the block slides (a) up the wall and (b) down the wall.

*64. GO A block is pressed against a vertical wall by a force P, as the drawing shows. This force can either push the block upward at a constant ve- locity or allow it to slide downward at a constant velocity. The magnitude of the force is different in the two cases, while the directional angle 0 is the same. Kinetic friction exists between the block and the wall, and the coefficient of kinetic friction is 0.250. The weight of the block is 39.0 N, and the directional angle for the force P is 0 = 30.0°. Determine the magnitude of P when the block slides (a) up the wall and (b) down the wall.

University Physics Volume 1

18th Edition

ISBN:9781938168277

Author:William Moebs, Samuel J. Ling, Jeff Sanny

Publisher:William Moebs, Samuel J. Ling, Jeff Sanny

Chapter6: Applications Of Newton's Laws

Section: Chapter Questions

Problem 47P: (a) What is the maximum frictional force in the knee joint of a person who supports 66.0 kg of her...

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