# Physics. Work Problem?

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A single force acts on a 2.5 kg particle-like object in such a way that the position of the object as a function of time is given by x = 3.8t - 1.7t2 + 0.95t3, with x in meters and t in seconds. Find the work done on the object by the force from t = 0 to t = 8.9 s.

my answer was 488.72 J but it was wrong.

A single force acts on a 2.5 kg particle-like object in such a way that the position of the object as a function of time is given by x = 3.8t - 1.7t2 + 0.95t3, with x in meters and t in seconds. Find the work done on the object by the force from t = 0 to t = 8.9 s.

my answer was 488.72 J but it was wrong.

##### 1 Answer

Mar 15, 2018

Work done by an external force = change in kinetic energy.

Given,

So,

So,using this equation,we get,at

And at

So,change in kinetic energy =

Putting the given values we get,