TS EAMCET 5-Aug-2021 Shift 1 Question Paper

Given,
Initial efficiency of Carnot engine, η1=50%.
Temperature of sink,T2=500K.
Final efficiency of Carnot engine, η2=80%.
T1 and T1f be the initial and final temperature of source.
As we know that,
‌η‌‌=1−‌

T2

T1

∴‌η1‌‌=‌

50

100

=1−‌

500

T1i

⇒‌‌

500

T1i

‌‌=1−‌

1

2

⇒‌

500

T1i

=‌

1

2

⇒‌T1i‌‌=1000K
‌‌ Similarly, ‌‌η2‌‌=1−‌

T2

T1f

⇒‌‌

80

100

‌‌=1−‌

500

T1f

⇒‌‌

500

T1

‌‌=1−‌

80

100

=‌

20

100

=‌

1

5

⇒‌T1f‌‌=2500K
‌⇒‌ Change in temperature, ‌∆T=T1f−T1i
‌‌‌=2500−1000=1500K