AP EAMCET2015PhysicsThermodynamics
A gas does 4.5 ~J of external work during adiabatic expansion. If its temperature falls by 2 ~K , then its internal energy will be
Options
- Aincreased by 4.5 ~J
- Bdecreased by 4.5 ~J
- Cdecreased by 2.25 ~J
- Dincreased by 9.0 ~J
Correct answer
B. decreased by 4.5 ~J
Step-by-step solution
From first law of thermodynamics, aligned & d Q=d U+d W & d U=-d W [In adiabatic process d Q=0 ] & d U=-4.5 ~J aligned As, the temperature falls so internal energy will decrease by 4.5 ~J