A force of 100 N is used to move a chair 2 m. How much work is done
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200 J

Explanation:

In the case of a rectilinear movement, the work is calculated as the product of Force (N) * movement (m). In your case, unless the angle between the force vector and the displacement vector is different from 0, the work is:

100 N * 2 m = 200 J

the reason is because the moon has some form of gravity, and that gravity pulls the ocean tides.

distance = 150m

displ = root (50 ^2 + 100^2)

root(2500+10000)

root 125000