A man lifts a 1 kg box from the floor, moves it 5 meters, then places it on a shelf 1 meter from the floor. Four students in physics class attempt to explain how much work was done on the box. Which student's explanation is best? The potential energy of the box on the floor was zero and now it is 10 j because PE = mgh. Work is the change in energy. Therefore, ten joules of work was done on Student 1: the box. The box weighed 10 N becauseFw= mg. A force was exerted of 10 N for 1 m while lifting the box. Force times distance equals work, so, ten joules of work was done on Student 2: the box. You are forgetting the box was moved 5 m while it was being held. That must have been work too. So, more than ten joules of work was done on the box. Student 3: Student 4: No! No! No! Work is the change in kinetic energy. The box started out at rest and ended up on the shelf at rest, so there was no change in kinetic energy. Don't overlook the fact that gravity was doing negative work on the box while the person moving the box was doing positive work on the box. Therefore, no work was done on the box!

A man lifts a 1 kg box from the floor, moves it 5 meters, then places it on a shelf 1 meter from the floor. Four students in physics class attempt to explain how much work was done on the box. Which student's explanation is best? The potential energy of the box on the floor was zero and now it is 10 j because PE = mgh. Work is the change in energy. Therefore, ten joules of work was done on Student 1: the box. The box weighed 10 N becauseFw= mg. A force was exerted of 10 N for 1 m while lifting the box. Force times distance equals work, so, ten joules of work was done on Student 2: the box. You are forgetting the box was moved 5 m while it was being held. That must have been work too. So, more than ten joules of work was done on the box. Student 3: Student 4: No! No! No! Work is the change in kinetic energy. The box started out at rest and ended up on the shelf at rest, so there was no change in kinetic energy. Don't overlook the fact that gravity was doing negative work on the box while the person moving the box was doing positive work on the box. Therefore, no work was done on the box!

Name: A man lifts a 1 kg box from the floor, moves it 5 meters, then places
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Description: A man lifts a 1 kg box from the floor, moves it 5 meters, then places it on a shelf 1 meter from thefloor. Four students in physics class attempt to explain how much work was done on the box. Whichstudent's explanation is best?Student 1:The potentia

College Physics

11th Edition

ISBN:9781305952300

Author:Raymond A. Serway, Chris Vuille

Publisher:Raymond A. Serway, Chris Vuille

Chapter5: Energy

Section: Chapter Questions

Problem 40P: (a) A block with a mass m is pulled along a horizontal surface for a distance x by a constant force...

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