We consider a thermodynamic system. If Δ U represents the increase in its internal energy and W the work done by the system, which of the following statements is true?

Question

We consider a thermodynamic system. If Δ U represents the increase in its internal energy and W the work done by the system, which of the following statements is true? (A) Δ U=-W in an adiabatic process (B) Δ U=W in an isothermal process (C) Δ U=-W in an isothermal process (D) Δ U=W in an adiabatic process

Tardigrade Admin · Accepted Answer

According to the first law of thermodynamics Δ Q=Δ U+Δ W In adiabatic process Δ Q=0, hence d U=-dW

Q. We consider a thermodynamic system. If $Δ U$ represents the increase in its internal energy and $W$ the work done by the system, which of the following statements is true?

$Δ U = - W$ in an adiabatic process

$Δ U = W$ in an isothermal process

$Δ U = - W$ in an isothermal process

$Δ U = W$ in an adiabatic process

According to the first law of thermodynamics
$Δ Q = Δ U + Δ W$
In adiabatic process $Δ Q = 0$ , hence $d U = - d W$

Q. We consider a thermodynamic system. If ΔU represents the increase in its internal energy and W the work done by the system, which of the following statements is true?

ΔU=−W in an adiabatic process

ΔU=W in an isothermal process

ΔU=−W in an isothermal process

ΔU=W in an adiabatic process