Question

A body of mass 20 kg at rest a force of 5 newton is applied on it calculate work done in first second

Answer 1

hope it helps!..........

Answer 2

Answer:

W.D=0.625 J

Explanation:

Since we have given a body of mass 20 kg at rest a force of 5 Newton is applied on it.

So,F=ma

5=20a

$a=0.25 m/s^{2}$.

We need to find the work done in first second.

So,we know the displacement in nth second.

$S_{n}=u+\dfrac{a(2n-1)}{2}$

Since initital velocity is zero.

So,we are calculating the displacement in first second.

$S_{1}=0+\dfrac{0.25(2-1)}{2}$

$S_{1} =0.125 m$

So, work done in first second is

$W.D=Force\times Displacement\\\\W.D=5\times 0.125\\\\W.D=0.625 J$