Question 459: Thermodynamics & KTG

Question

Helium gas goes through a cycle $$ABCD$$ (consisting of two isochoric and isobaric lines) as shown in figure efficiency of this cycle is nearly : (Assume the gas to be close to ideal gas)

Accepted Answer

Heat given to system $$ = {\left( {n{C_v}\Delta T} ight)_{A 	o B}} + {\left( {n{C_p}\Delta T} ight)_{B 	o C}}$$
$$ = {\left[ {{3 \over 2}\left( {nR\Delta T} ight)} ight]_{A 	o B}} + {\left[ {{5 \over 2}\left( {nR\Delta T} ight)} ight]_{B 	o C}}$$
$$ = {\left[ {{3 \over 2} 	imes {V_0}\Delta P} ight]_{A 	o B}} + {\left[ {{5 \over 2} 	imes 2{P_0} 	imes {V_0}} ight]_{B 	o C}}$$
$$ = {{13} \over 2}{P_0}{V_0}$$
and $${W_0} = {P_0}{V_0}$$
$$\eta  = {{Work} \over {heat\,\,given}}$$
$$ = {{{P_0}{V_0}} \over {{{13} \over 2}{P_0}{V_0}}} 	imes 100$$
$$ = 15.4\% $$

Answer

$$15.4\% $$

Answer

$$9.1\% $$

Answer

$$10.5\% $$

Answer

$$12.5\% $$

Thermodynamics & KTG

Helium gas goes through a cycle $ABCD$ (consisting of two isochoric and isobaric lines) as shown in figure efficiency of this cycle is nearly : (Assume the gas to be close to ideal gas)

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