42.0-kg projectile is fired at an angle of 30.0° above the horizontal with an initial speed of 136 m/s from the top of a cliff 138 m above level ground, where the ground is taken to be y = 0. (a) What is the initial total mechanical energy of the projectile? (Give your answer to at least three significant figures.) 445216.800 J (b) Suppose the projectile is traveling 96.4 m/s at its maximum height of y = 331 m. How much work has been done on the projectile by air friction? |-113825.04 (c) What is the speed of the projectile immediately before it hits the ground if air friction does one and a half times as much work on the projectile when it is going down as it did when it was going up? 117.1

42.0-kg projectile is fired at an angle of 30.0° above the horizontal with an initial speed of 136 m/s from the top of a cliff 138 m above level ground, where the ground is taken to be y = 0. (a) What is the initial total mechanical energy of the projectile? (Give your answer to at least three significant figures.) 445216.800 J (b) Suppose the projectile is traveling 96.4 m/s at its maximum height of y = 331 m. How much work has been done on the projectile by air friction? |-113825.04 (c) What is the speed of the projectile immediately before it hits the ground if air friction does one and a half times as much work on the projectile when it is going down as it did when it was going up? 117.1

Physics for Scientists and Engineers, Technology Update (No access codes included)

9th Edition

ISBN:9781305116399

Author:Raymond A. Serway, John W. Jewett

Publisher:Raymond A. Serway, John W. Jewett

Chapter8: Conservation Of Energy

Section: Chapter Questions

Problem 8.23P: A 5.00-kg block is set into motion up an inclined plane with an initial speed of i = 8.00 m/s (Fig....

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At the start of a basketball game, a referee tosses a basketball straight into the air by giving it some initial speed. After being given that speed, the ball reaches a maximum height of 4.25 m above where it started. Using conservation of energy, find a. the balls initial speed and b. the height of the ball when it has a speed of 2.5 m/s.
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