help with question number 5,6, and 7 TOpic:1.What work is done by a girl who pushes a box along the floor with a force of 80newtons for a distance of 10 meters?A boy raises a 20 kg rock to a height of 1.5 meters.a) What force does the boy use to raise the rock?b) What work does the boy do in raising the rock?How much work is done on a downhill skier by an average breaking force of 9.8 x102 newtons to stop her in a distance of 10 meters?Which action would require no work to be done on an object?2.3.4.1. lifting the object from the floor to the ceiling2. pushing the object along a horizontal floor against a frictional force3. decreasing the speed of the object'until it comes to rest4. holding the object stationary above the groundA student pulls a box across a horizontal floor at a constant speed of 4.0 m/s byexerting a constant horizontal force of 45 newtons. How much work does thestudent do against friction in moving the box 5.5 meters across the floor?A student does 300 J of work pushing a cart 3.0 meteTs due east and then does 400J of work pushing the cart 4.0°meters due north. What is the total amount of workdone by the student?A student pulls a block 3.0 meters along a horizontal surface at constant velocity.The diagram below shows the components of the force exerted on the block bythe student.5.6.7.StringHorizontalSurfaceA 8.0 N3.0 mHow much work is done againstfriction?

Speed (v) = 4 m/s Force (F) = 45 N distance (s) = 3 m

4. holding the object A student pulls a box across a horizontal floor at a constant speed of 4.0 m exerting a constant horizontal force of 45 newtons. How much work does the student do against friction in moving the box 5.5 meters across the floor? 5. fuork pushing a cart 3.0 meters due east and then does 400 omount of work

4. holding the object A student pulls a box across a horizontal floor at a constant speed of 4.0 m exerting a constant horizontal force of 45 newtons. How much work does the student do against friction in moving the box 5.5 meters across the floor? 5. fuork pushing a cart 3.0 meters due east and then does 400 omount of work

College Physics

11th Edition

ISBN:9781305952300

Author:Raymond A. Serway, Chris Vuille

Publisher:Raymond A. Serway, Chris Vuille

Chapter5: Energy

Section: Chapter Questions

Problem 12CQ: For each of the situations given, state whether frictional forces do positive, negative, or zero...

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