BITSAT 2022 Paper

Let the insulated container has n moles of the monoatomic gas. The loss of kinetic energy of the gas,
ΔEK=

1

2

(mv)v2
If the change in temperature of the gas is ΔT, then heat gained by the gas is,
ΔQ=

3

2

nRΔT
Now, according to question,
ΔQ=ΔEK

3

2

nRΔT=

1

2

mnv2
⇒ΔT=

mv2

3R