Question

The internal energy of a system increases by $60\mathrm{J}$ when $140\mathrm{J}$ of heat is added to the gaseous system. The amount of work done would be:

Answer 1

Given data:-

Given that, the change in internal energy : $\mathrm{dU}=60\mathrm{J}$

and heat added to the gaseous system : $\mathrm{dq}=140\mathrm{J}$

Step 1: First law of thermodynamics:-

According to the first law of thermodynamics:

$\mathrm{dU}=\mathrm{dq}-\mathrm{dw}$

By rearranging the formula, we can get:

$\mathrm{dw}=\mathrm{dq}-\mathrm{dU}$
Step 2: Substitute the value for calculating the value of work done:-
Now by substituting the values we can calculate the value of work done as:

$\therefore \mathrm{dw}=140\mathrm{J}-60\mathrm{J}=80\mathrm{J}$

Hence, the amount of work done has been calculated as: $80\mathrm{J}$.