Question

If a boy is sleeping, he is doing work?
A. true
B. false

Answer 1

Hint: When a person is in sleep, there is no loss of energy from the body. The displacement of the body will also be zero. These all will affect the work done by the body. This information will help you in solving the question.

Complete answer:
When a boy is in sleep he is resting at the same position without any movement from there. As we all know, the work done is given as the equation,
$W=F\cdot S$
Where $F$be the force acting on the body and $S$ be the displacement of the object.
Here we can see that there is no displacement for the body from the place he is sleeping. The change in the position will be zero. Therefore the work done by the body will be calculated as,
$\begin{align}
  & W=F\cdot S \\
 & \Rightarrow W=F\times 0=0J \\
\end{align}$
Therefore the boy who is sleeping at the same position will be doing zero work and hence the statement can be false.
And also we can say that the body is not spending any sort of energy while sleeping. The body tends to be in a minimal state of energy for the complete rest of the body. As we all know, the work done can be called as the energy spent during its motion. As here, the energy spent by the body in motion is zero, the work done by the body will be zero. This also says that the given statement of the boy sleeping is wrong.

So, the correct answer is “Option B”.

Note:
In accordance to the work-energy theorem, the resultant work on a body will result in a variation in the kinetic energy of the object. The net work done is the difference between the final kinetic energy and initial kinetic energy. The work done is a scalar quantity also.