An ideal gas undergoes cyclic process as shown in density pressur… - Vidyadip

MCQ

An ideal gas undergoes cyclic process as shown in density pressure graph. During the process $AB$ the work done $|W_{AB}| = 70\,J$ . During the process $BC$, the gas absorbs $150\,J$ of heat. During the process $CA$ , gas undergoes expansion and does $210\,J$ of work

A
The efficiency of cyclic process is $33\%$
✓
The efficiency of cyclic process is $66\%$
C
The process $CA$ is adiabatic
D
The process $BC$ is isothermal

✓

Answer

Correct option: B.

The efficiency of cyclic process is $66\%$

b

	$Q$	$\Delta U$	$W$
$AB$	$-70$	$0$	$-70$
$BC$	$150$	$150$	$0$
$CA$	$60$	$-150$	$210$

$\eta=\frac{140}{210} \times 100 \%=60 \%$

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