Question 979: Thermodynamics & KTG

Question

An engine has an efficiency of 1/6. When the temperature of sink is reduced by 62
o
C, its efficiency is doubled. Temperatures of the source is

Accepted Answer

Since efficiency of engine is $$\eta  = 1 - {{{T_2}} \over {{T_1}}}$$
According to problem,
$${1 \over 6} = 1 - {{{T_2}} \over {{T_1}}}$$   ...(i)
When the temperature of the sink is reduced by 62ÃÂ°C, its efficiency is doubled
$$2\left( {{1 \over 6}} \right) = 1 - {{{T_2} - 62} \over {{T_1}}}$$   ...(ii)
Solving (i) and (ii)
T
2
= 372 K
T
1
= 99ÃÂ°C = Temperature of source.

Answer

37
o
C

Answer

62
o
C

Answer

99
o
C

Answer

124
o
C.

Thermodynamics & KTG

An engine has an efficiency of 1/6. When the temperature of sink is reduced by 62 o C, its efficiency is doubled. Temperatures of the source is

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