30. A crate on rollers is being pushed without frictional loss of energy across the floor of a freight car (see the following figure). The car is moving to the right with a constant speed vo. If the crate starts at rest relative to the freight car, then from the work- energy theorem, Fd = mv² /2, where d, the distance the crate moves, and v, the speed of the crate, are both measured relative to the freight car. (a) To an observer at rest beside the tracks, what distance d'is the crate pushed when it moves the distance d in the car? (b) What are the crate's initial and final speeds vo'and v’as measured by the observer beside the tracks? (c) Show that Fd'= m(v)²/2 – m(v'o)²/2 and, consequently, that work is equal to the change in kinetic energy in both reference systems. Vo

30. A crate on rollers is being pushed without frictional loss of energy across the floor of a freight car (see the following figure). The car is moving to the right with a constant speed vo. If the crate starts at rest relative to the freight car, then from the work- energy theorem, Fd = mv² /2, where d, the distance the crate moves, and v, the speed of the crate, are both measured relative to the freight car. (a) To an observer at rest beside the tracks, what distance d'is the crate pushed when it moves the distance d in the car? (b) What are the crate's initial and final speeds vo'and v’as measured by the observer beside the tracks? (c) Show that Fd'= m(v)²/2 – m(v'o)²/2 and, consequently, that work is equal to the change in kinetic energy in both reference systems. Vo

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Description: 30. A crate on rollers is being pushed without frictional loss of energy across the floor of a freight car (see the following figure).The car is moving to the right with a constant speed vo. If the crate starts at rest relative to the freight car, t

College Physics

10th Edition

ISBN:9781285737027

Author:Raymond A. Serway, Chris Vuille

Publisher:Raymond A. Serway, Chris Vuille

Chapter5: Energy

Section: Chapter Questions

Problem 82AP: A hummingbird is able to hover because, as the wings move downward, they exert a downward force on...

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