Question

JEE MAINS PHYSICS QUESTION SEPTEMBER 2020

Answer 1

ANSWER.

=> internal energy of 1 mole of temperature

is = 3RT.

Option [ A ] is correct answer.

EXPLANATION.

$\sf \to \: a \: triatomic \: molecule \: in \: the \: shape \\ \\ \sf \to \: energy \: of \: any \: mole \: of \: gas \: = \frac{degree \: of \: freedom}{2} \times nrt \\ \\ \sf \to \: \frac{6}{2} \times nrt \implies \: 3nrt$

$\sf \to \: \green{{ \underline{some \: more \: information}}} \\ \\ \sf \to \: atomicity \: of \: gas \: \\ \\ \sf \to \: 1) = monoatomic \: \\ \\ \sf \to \: example \: = he , ne , ar \\ \\ \sf \to \: degree \: of \: freedom \: = 3translation$

$\sf \to \: 2) = diatomic \: and \: triatomic \:(linear) \\ \\ \sf \to \: example \: = h_{2} , n_{2} , o_{2} , co , co_{2} \\ \\ \sf \to \: 3 \: translation \: + \: 2 \: rotational \: = 5$

$\sf \to \: triatomic \: (non \: linear) \\ \\ \sf \to \: example = h_{2}o , so_{2} \\ \\ \sf \to \: degree \: of \: freedom \\ \\ \sf \to \: 3translation \: + 3rotational \: = 6$

Answer 2

$\implies \:internal \:energy \:of \:1 \:mole \:of \:temperature$

$\implies \:is \:= \:3RT.$

$\implies \:Option \:[ A ] \:is \:correct \:answer.$