Question

x joule of work is done on a gas to reduce it volume by compressing it. If this change
is done under adiabatic condition, calculate the :
(a) change in internal energy of the gas
(b)
amount of heat absorbed by the gas

answer fast pls​

Answer 1

Given:

x joule of work is done on a gas to reduce it volume by compressing it. This change is performed under adiabatic condition.

To find:

• Change in internal energy?
• Amount of heat absorbed?

Calculation:

In this type of questions, it is best to apply the 1st Law of Thermodynamics.

• Now, since the thermodynamic process is adiabatic in nature, the system will not be able to exchange heat with the surroundings. Hence ∆Q will be zero.

So, amount of heat absorbed = 0 Joules.

Now, work done is -x (negative sign to be considered, because gas is compressed).

$\therefore$ ∆Q = ∆U + W

=> 0 = ∆U + W

=> ∆U = -W

=> ∆U = -(-x)

=> ∆U = +x

So, internal energy change is +x.