Question

A scientist claims to have developed a heat engine
working between 27°C and 727°C with efficiency x.
Which of the following values of x will make his
claim right?
(1) 60%
R (2) 75%
(3) 80%
(4) 85%​

Answer 1

Answer :

$\bullet$ Note: Check this attachment!

Answer 2

Given:- Temperature 1 (T1) = 727 +273 = 1000 k

Temperature 2 ( T1 ) = 27 + 273 = 300 k

Efficiency= x

Find:- efficiency (x)

As we know the formula to find efficiency is

x = 1- T2

T1

x = 1 - 300

1000

x = 1000 - 300

1000

x = 700

1000

x = 0.7

Efficiency in percentage,

x = 0.7 × 100

x= 70%

So the efficiency of a heat engine is 70%