Question #4 Key Concepts:. Work: W F. |F||s|cos0• Power: P %3D. Mechanical Energy (Kinetic and Potential)Reinforcement:1. A construction site worker is tasked with transporting 55 blocks to the other side of the site. If the Truck bedis 1.7 m off the ground, how much work is done to lift all the blocks to the truck bed?I2. A dog is pulling a sled up a hill. If the rope used to pull the sled is subtended by an angle of 13 and the dogis pulling with a force of 555 N, how work is done if its pulled 30 m?3. How long would it take a 3.2-kW motor to raise a 175-kg piano to an apartment 30 m off the ground?4. You are tasked with designing a new motor that is based off of an older model. The new model completes 1.5times as much work in half the time. What would the new models power be rated as?

Given data: Work done by new model (W') = 1.5W Time taken by new model (t') = 0.5t Required: New…

Answered: You are tasked with designing a new…

You are tasked with designing a new motor that is based off of an older model. The new model completes 1.5 times as much work in half the time. What would the new models power be rated as?

Physics for Scientists and Engineers with Modern Physics

10th Edition

ISBN:9781337553292

Author:Raymond A. Serway, John W. Jewett

Publisher:Raymond A. Serway, John W. Jewett

Chapter7: Energy Of A System

Section: Chapter Questions

Problem 25P: Review. You can think of the workkinetic energy theorem as a second theory of motion, parallel to...

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In the Back to the Future movies (https://openstaxcollege.org/l/2lbactofutclip), a DeLorean car of mass 1230 kg travels at 88 miles per hour to venture back to the future. (a) What is the kinetic energy of the DeLorean? (b) What spring constant would be needed to stop this DeLorean in a distance of 0.1m?
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