Question

In a diesel engine, the cylinder compresses air from S.T.P. to about `1/14` the original volume and a pressure of 40 atmospheres. The temperature of compressed air is ______

Options

• 780 K

• 580 K

• 853 K

• 1126 K

Answer 1

In a diesel engine, the cylinder compresses air from S.T.P. to about `1/14` the original volume and a pressure of 40 atmospheres. The temperature of compressed air is 780 K.

Explanation:

At S.T.P.,

T₁ = 273 K and P₁ = 1 atm

Given that, `"V"_2 = "V"_1/14`; and P₂ = 40 atm

Being the same gas compressed, n = constant Equation of state

⇒ `("P"_1"V"_1)/"T"_1 = ("P"_2"V"_2)/"T"_2`

∴ `"T"_2 = ("P"_2"V"_2)/("P"_1"V"_1) xx "T"_1 = (40 xx "V"_1)/(14 xx 1 xx "V"_1) xx 273`

∴ `"T"_2 = 780` K