In an adiabatic expansion of a gas,

Name: Exam Paper Generator | JEE NEET Paper Generator | Vedclass
Brand: Vedclass
Rating: 5 (35 reviews)

Question

(B) In an adiabatic process,there is no exchange of heat with the surroundings,so $dQ = 0$.According to the first law of thermodynamics,$dQ = dU + dW$

Vedclass · Accepted Answer

Its temperature falls

Vedclass · Answer

(B) In an adiabatic process,there is no exchange of heat with the surroundings,so $dQ = 0$.According to the first law of thermodynamics,$dQ = dU + dW$,where $dU$ is the change in internal energy and $dW$ is the work done by the gas.Since $dQ = 0$,we have $dU = -dW$.In an expansion,the gas does work on the surroundings,so $dW > 0$.This implies $dU Since the internal energy of an ideal gas is directly proportional to its temperature $(U \propto T)$,a decrease in internal energy leads to a decrease in temperature.Therefore,in an adiabatic expansion,the temperature of the gas falls.

Similar Questions

$A$ cycle tyre bursts suddenly. This process represents an:

You feel refreshed by taking a shower in summer but not in winter. Why?

Five moles of hydrogen initially at $STP$ is compressed adiabatically so that its temperature becomes $673 \, K$. The increase in internal energy of the gas, in kilo joule is $(R=8.3 \, J/mol-K; \gamma=1.4$ for diatomic gas$)$

$5.6 \text{ liter}$ of helium gas at $STP$ is adiabatically compressed to $0.7 \text{ liter}$. Taking the initial temperature to be $T_1$,the work done in the process is

Vedclass Test Series

Exam Paper Generator

Online Exam Module