Q17) Two identical copper blocks of mass m=1.5 kg, block L at temperature Ta = 60 °C and block R at temperature TiR-20° C. The blocks are in a thermally insulated box and are separated by an insulating shutter. When we lift the shutter, the blocks eventually come to the equilibrium temperature T-40°C. The net entropy change (in J/K) of the two-block system during this irreversible process is: (The specific heat of copper is 386 J/kg. K) a) 0 b)-74.1 c) -2.4 d) +74.1 e) +2.4 Q18) How much energy (in 10 J) must be transferred as heat for a reversible isothermal expansion of an ideal gas at 132°C if the entropy of the gas increases by 46.0 J/K? a) 1.86 b)-1.86 c) 7.21 d) -7.21 e) 2.67

Q17) Two identical copper blocks of mass m=1.5 kg, block L at temperature Ta = 60 °C and block R at temperature TiR-20° C. The blocks are in a thermally insulated box and are separated by an insulating shutter. When we lift the shutter, the blocks eventually come to the equilibrium temperature T-40°C. The net entropy change (in J/K) of the two-block system during this irreversible process is: (The specific heat of copper is 386 J/kg. K) a) 0 b)-74.1 c) -2.4 d) +74.1 e) +2.4 Q18) How much energy (in 10 J) must be transferred as heat for a reversible isothermal expansion of an ideal gas at 132°C if the entropy of the gas increases by 46.0 J/K? a) 1.86 b)-1.86 c) 7.21 d) -7.21 e) 2.67

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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