Question 359: Thermodynamics & KTG

Question

To raise the temperature of a certain mass of gas by 50
o
C at a constant pressure, 160 calories of
heat is required. When the same mass of gas is cooled by 100
o
C at constant volume, 240 calories
of heat is released. How many degrees of freedom does each molecule of this gas have (assume
gas to be ideal)?

Accepted Answer

$$160 = n{C_p}50$$ ....(i)
$$240 = n{C_v}100$$ ....(ii)
Dividing (i) by (ii), we get
$${{160} \over {240}} = {{{C_p}} \over {{C_v}}} 	imes {1 \over 2}$$
$$ \Rightarrow $$ $${{{C_p}} \over {{C_v}}}$$ = $$ {4 \over 3}$$
We know,
$$ \gamma  = {{{C_p}} \over {{C_v}}} = 1 + {2 \over f} = {4 \over 3}$$
$$ \Rightarrow f = 6$$

Answer

6

Answer

7

Answer

5

Answer

3

Thermodynamics & KTG

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