Question

A floating ice block is pushed through a displacement d = (14 m) i hat - (11 m) j along a straight embankment by rushing water, which exerts a force F = (158 N) i hat - (179 N) j on the block. How much work does the force do on the block during the displacement?

Answer 1

Explanation:

Given that,

Displacement in ice block, $d=14i-11j$

Force exerted by water, $F=158i-179j$

To find,

Work done by the force during the displacement.

Solve,

We know that the product of force and displacement is called work done. It is also equal to the dot product of force and displacement as :

$W=F.d$

$W=(158i-179j).(14i-11j)$

We know that, i.i = j.j = k.k = 1

$W=2212+1969=4181\ J$

So, the work done by the force on the block during the displacement is 4181 Joules.