Question

A floating ice block is pushed through a displacement d = (23 m) i - (9 m) j along a straight embankment by rushing water, which exerts a force F = (200 N) i - (149 N) j on the block. How much work does the force do on the block during the displacement?

Answer 1

Answer:

Work done, W = 5941 joules

Explanation:

It is given that,

Force exerted on the block, $F=(200i-149j)\ N$

Displacement, $x=(23i-9j)\ m$

Let W is the work done by the force do on the block during the displacement. Its formula is given by :

$W=F.d$

$W=(200i-149j){\cdot} (23i-9j)$                    

Since, i.i = j.j = k.k = 1

$W=4600+1341$

W = 5941 joules

So, the work done by the force do on the block during the displacement is 5941 joules. Hence, this is the required solution.

Answer 2

Answer:

Work = 5941 J

Explanation:

As we know that work done is given by the equation

$W = F. d$

here we know that

$F = (200 N)\hat i - (149 N) \hat j$

also we have

$d = (23m) \hat i - (9 m)\hat j$

now from above formula we have

$W = (200 N\hat i - 149 N \hat j).(23 m\hat i - 9m \hat j)$

$W = 5941 J$