Q: A young Mr. Watford applies a force of 180N to a refrigerator on. kitchen floor.(adsbygoogle = window.adsbygoogle || []).push({});

Part (A):Find the net force on the refrigerator if the floor has a constant frictional force of 35N.

Ans:145N

Part (B): Calculate the acceleration of the refrigerator if it has a mass of 70kg.

Ans: 2.57 ms-2

Part (C) Calculate the kinetic energy of the fridge after it has been pushed 5.00m.

initial velocity = 0 ms-1

displacement = 5m

acceleration = 2.57 ms-2

mass = 70kg

time = ?

s = ut + 1/2at^2

v = u + at

Ek=1/2 mv^2

Substituting the given units into s = ut + 1/2at^2, I got time = 1.97s

Substituting the units into v = u + at, I got final velocity = 5.06 ms-1

And finally subbing the units into Ek= 1/2mv^2, I got Kinetic Energy = 896.13J.

I got one benefit of the doubt mark out of four possible marks, and if that was in an exam I would've got 0 marks as there are no benefit of the doubt marks.

Please reply asap I have an exam tomorrow.

Thanks

*ANSWERED*

E = W

W= Fs

=180 x 5 = 900J

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# Homework Help: Kinetic Energy Problem

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