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mash [69]
3 years ago
10

A student pulls a box across a horizontal floor at a constant speed of 4.0 meters per second by exerting a constant horizontal f

orce of 45 newtons. approximately how much work does the student do against friction in moving the box 5.5 meters across the floor?
Physics
2 answers:
ruslelena [56]3 years ago
8 0
Work = Force multiplied by the distance(or displacement)
Rainbow [258]3 years ago
5 0

Answer:

247.5N

Explanation:

A student pulls a box across a horizontal floor at a constant speed of 4.0 meters per second by exerting a constant horizontal force of 45 newtons. approximately how much work does the student do against friction in moving the box 5.5 meters across the floor?

DEFINITION OF TERMS

work done is the product of force and distance. if the student pulls the box without covering a distance, e asnt done any form of work.

force is tat which tends to change a body's state of rest or uniform motion  in a straight line.

w=f*d

45*5.5

247.5Nm

the frictional force between the object and the ground will be in the opposite direction to the force applied

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Explanation:

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F_{net}=Ma\\Mg(\sin \theta-\mu_s \cos \theta)=Ma\\\therefore a=g(\sin \theta-\mu_s \cos \theta)------4

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