Thermodynamics - Result Question 42

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44. An engine has an efficiency of $1 / 6$. When the temperature of sink is reduced by $62^{\circ} C$, its efficiency is doubled. Temperature of the source is

======= ####44. An engine has an efficiency of $1 / 6$. When the temperature of sink is reduced by $62^{\circ} C$, its efficiency is doubled. Temperature of the source is

3e0f7ab6f6a50373c3f2dbda6ca2533482a77bed:content/english/neet-pyq-chapterwise/physics/thermodynamics/thermodynamics—result-question-42.md (a) $37^{\circ} C$

(b) $62^{\circ} C$

(c) $99^{\circ} C$

(d) $124^{\circ} C$

[2007]

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Answer:

Correct Answer: 44. (c)

Solution:

  1. (c) Since efficiency of engine is $\eta=1-\frac{T_2}{T_1}$ According to problem,

$\frac{1}{6}=1-\frac{T_2}{T_1}$

When the temperature of the sink is reduced by $62^{\circ} C$, its efficiency is doubled

$2(\frac{1}{6})=1-\frac{T_2-62}{T_1}$

Solving (1) and (2)

$T_2=372 K$

$T_1=99^{\circ} C=$ Temperature of source.