Example 24: Figure 3.11(a) shows a rope running through a pulley at P and bearing a weight W at one end. The other end is held 5 ft above the ground in the hand M of a worker. Suppose the pulley is 25 ft above ground, the rope is 45 ft long, and the worker is walking rapidly away from the vertical line PW at the rate of 6 ft/sec. How fast is the weight being raised when the worker's hand is 21 ft away from PW ? 20 ft W W м 6 f/sec M 5ft X. (a) (b) Figure 3.11: A worker at M walks to the right pulling the weight W upwards as the rope moves through the pulley P (Example 24).

Example 24: Figure 3.11(a) shows a rope running through a pulley at P and bearing a weight W at one end. The other end is held 5 ft above the ground in the hand M of a worker. Suppose the pulley is 25 ft above ground, the rope is 45 ft long, and the worker is walking rapidly away from the vertical line PW at the rate of 6 ft/sec. How fast is the weight being raised when the worker's hand is 21 ft away from PW ? 20 ft W W м 6 f/sec M 5ft X. (a) (b) Figure 3.11: A worker at M walks to the right pulling the weight W upwards as the rope moves through the pulley P (Example 24).

University Physics Volume 1

18th Edition

ISBN:9781938168277

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

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

Chapter2: Vectors

Section: Chapter Questions

Problem 2.9CYU: Check Your Understanding Suppose that Balto in Example 2.10 leaves the game to attend to more...

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