Question

A carnot engine has the same efficiency between 800 K to 500 K and x K to 600 K. The value of x is

• A. 1000 K
• B. 960 K
• C. 846 K
• D. 754 K

Answer 1

Answer: (B)

960 K

Answer 2

In first case, $(\eta_{1}) = 1 - \frac{500}{800} = \frac{3}{8}$

and in second case, $(\eta_{2}) = 1 - \frac{600}{x}$

Since $\eta_{1} = \eta_{2},$ therefore $\frac{3}{8} = 1 - \frac{600}{x}$

or $\frac{600}{x} = 1 - \frac{3}{8} = \frac{5}{8}$or$x = \frac{600 \times 8}{5} = 960K$