Work

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SAT Subject Test in Physics › Work

Questions 1 - 2

1

A crate is pushed across the floor. If of force was used to achieve this motion, how much work was done?

Explanation

The formula for work is:

Given the values for force and distance, we can calculate the work done.

Note that no work is done by the force of gravity or the weight of the box, since the vertical position does not change.

2

A man moves a crate by pulling a rope at a angle with the ground and a constant force of . How much work has the man performed after pulling the crate ?

Explanation

Work is given by the equation:

$W=Fd\cos\theta$

We know the force with which the man pulls, the angle, and the distance that the crate travels. Using these values we can solve the equation for the work done.

$W=(300N)(10m)\cos(60^o)$

$W=(3000J)(\frac{1}{2})$

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