Question

Force acting on a particles moving in a straight line varies with the velocity $v$ of the particles as $F=K$ where $K$ is a constant. The work done by this force in time $t$ is

• A. $\frac{K}{v^2}t$
• B. $2Kt$
• C. all the above
• D. None of these

Answer 1

The correct option is D None of these

We know work done$W=Fs$-----------(A) where F=force and s=displacement.

Given $F=K$

Also we know $v=\frac{s}{t}$ where v=velocity, s= distance covered and t= time taken to cover that distance.

$s=vt$

Reducing the above value in A we get,

$dw=Fvdt$

Now integrating the above equation with respect to time,

$W=Fvt$