Two blocks of the same metal having same mass and at temperature T1 and T2, respectively. are brought in contact with each other and allowed to attain thermal equilibrium at constant pressure. The change in entropy, Δ S, for this process is :

Question

Two blocks of the same metal having same mass and at temperature T1 and T2, respectively. are brought in contact with each other and allowed to attain thermal equilibrium at constant pressure. The change in entropy, Δ S, for this process is : (A) 2CP ln ((T1+T2/4T1T2)) (B) 2CP ln [((T1 +T2)(1/2)/T1T2)]  (C) CP ln [((T1+T2)2/4T1T2)] (D) 2CP ln [(T1+T2/2T1T2)]

Tardigrade Admin · Accepted Answer

Correct answer is (c) CP ln [((T1+T2)2/4T1T2)]

Q. Two blocks of the same metal having same mass and at temperature $T_{1}$ and $T_{2}$ , respectively. are brought in contact with each other and allowed to attain thermal equilibrium at constant pressure. The change in entropy, $Δ S$ , for this process is :

$2 C_{P} l n (\frac{T _{1} + T _{2}}{4 T _{1} T _{2}})$

$2 C_{P} l n [\frac{( T _{1} + T _{2} ) ^{\frac{1}{2}}}{T _{1} T _{2}}]$

$C_{P} l n [\frac{( T _{1} + T _{2} ) ^{2}}{4 T _{1} T _{2}}]$

$2 C_{P} l n [\frac{T _{1} + T _{2}}{2 T _{1} T _{2}}]$

Correct answer is (c) $C_{P} l n [\frac{( T _{1} + T _{2} ) ^{2}}{4 T _{1} T _{2}}]$

Q. Two blocks of the same metal having same mass and at temperature T1​ and T2​, respectively. are brought in contact with each other and allowed to attain thermal equilibrium at constant pressure. The change in entropy, ΔS, for this process is :

2CP​ln(4T1​T2​T1​+T2​​)

2CP​ln[T1​T2​(T1​+T2​)21​​]

CP​ln[4T1​T2​(T1​+T2​)2​]

2CP​ln[2T1​T2​T1​+T2​​]