<h2>The work done = - 2 x 10⁴ J</h2>
Explanation:
In the first case , the volume is kept constant and pressure varies .
In isothermal process , the work done
W₁ = V x ΔP
here V is the volume of gas and ΔP is the change in pressure
Thus W₁ = 0
Because there is no change in volume , therefore displacement is zero .
In second case pressure is constant , but volume changes
Thus W₂ = P x ΔV
here P is the pressure and ΔV is the change in volume
Therefore W₂ = 4 x 10⁵ x 5 x 10⁻² = 2 x 10⁴ J
The total work done W = - 2 x 10⁴ J
Because the work done in compression is negative .
You are trying to convert mass to volume. That ain't working
Answer:

Explanation:
When top block is just or about to slide on the lower block then we can say that the frictional force on it will be maximum static friction
So we will have






now for the Net force on two blocks to move together


