Question 3: Thermodynamics & KTG

Question

In an isobaric process, the work done by a
di-atomic gas is 10 J, the heat given to the
gas will be

Accepted Answer

Given, for isobaric process,
Work done by a di-atomic gas
By ideal gas equation, at constant pressure,
$$p \Delta V=n R \Delta T$$ .... (i)
$$	herefore$$ Work done,
$$\begin{aligned}
& W=p \Delta V \
& W=n R \Delta T \quad 	ext{.... (ii)}
\end{aligned}$$
At constant pressure, heat given to gas is given by
$$Q=n C_p \Delta T$$ ..... (iii)
where, $$C_p=$$ specific heat at constant pressure
From Eqs. (ii) and (iii), we get
$$\frac{W}{Q}=\frac{n R \Delta T}{n C_p \Delta T}=\frac{R}{C_p}$$
$$\begin{aligned}
& =\frac{R}{\frac{(f+2) R}{2}} \quad\left[\because C_p=\frac{(F+2) R}{2}ight] \
\frac{W}{Q} & =\frac{2}{f+2} \quad[\because W=10 \mathrm{~J} 	ext { (given) }] \
\frac{10}{Q} & =\frac{2}{5+2} \quad[	ext { For di-atomic gas, } f=5] \
\Rightarrow \quad Q & =35 \mathrm{~J}
\end{aligned}$$

Answer

35 J

Answer

30 J

Answer

45 J

Answer

60 J

Thermodynamics & KTG

In an isobaric process, the work done by a di-atomic gas is 10 J, the heat given to the gas will be

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