A 44.0-kg projectile is fired at an angle of 30.0° above the horizontal with an initial speed of 140 m/s from the top of a cliff 146 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.)J(b) Suppose the projectile is traveling 99.2 m/s at its maximum height of y = 350 m. How much work has been done on the projectile by air friction?(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?m/s

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Description: A 44.0-kg projectile is fired at an angle of 30.0° above the horizontal with an initial speed of 140 m/s from the top of a cliff 146 m above level ground, where the ground is taken to be y = 0.(a) What is the initial total mechanical energy of the p

Write the given values with the suitable variables. m=44 kgθ=30°u=140 m/sh=146 m Here, m, θ, u, and…

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A 44.0-kg projectile is fired at an angle of 30.0° above the horizontal with an initial speed of 140 m/s from the top of a cliff 146 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.) (b) Suppose the projectile is traveling 99.2 m/s at its maximum height of y = 350 m. How much work has been done on the projectile by air friction? (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? m/s

A 44.0-kg projectile is fired at an angle of 30.0° above the horizontal with an initial speed of 140 m/s from the top of a cliff 146 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.) (b) Suppose the projectile is traveling 99.2 m/s at its maximum height of y = 350 m. How much work has been done on the projectile by air friction? (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? m/s

College Physics

1st Edition

ISBN:9781938168000

Author:Paul Peter Urone, Roger Hinrichs

Publisher:Paul Peter Urone, Roger Hinrichs

Chapter7: Work, Energy, And Energy Resources

Section: Chapter Questions

Problem 7PE: A shopper pushes a grocery cart 20.0 m at constant speed on level ground, against a 35.0 N...

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