1
JEE Main 2021 (Online) 20th July Evening Shift
MCQ (Single Correct Answer)
+4
-1
Change Language
The correct relation between the degrees of freedom f and the ratio of specific heat $$\gamma$$ is :
A
$$f = {2 \over {\gamma - 1}}$$
B
$$f = {2 \over {\gamma + 1}}$$
C
$$f = {{\gamma + 1} \over 2}$$
D
$$f = {1 \over {\gamma + 1}}$$
2
JEE Main 2021 (Online) 20th July Morning Shift
MCQ (Single Correct Answer)
+4
-1
Change Language
Consider a mixture of gas molecule of types A, B and C having masses mA < mB < mC. The ratio of their root mean square speeds at normal temperature and pressure is :
A
$${v_A} = {v_B} \ne {v_C}$$
B
$${1 \over {{v_A}}} > {1 \over {{v_B}}} > {1 \over {{v_C}}}$$
C
$${1 \over {{v_A}}} < {1 \over {{v_B}}} < {1 \over {{v_C}}}$$
D
$${v_A} = {v_B} = {v_C} = 0$$
3
JEE Main 2021 (Online) 20th July Morning Shift
MCQ (Single Correct Answer)
+4
-1
Change Language
The amount of heat needed to raise the temperature of 4 moles of rigid diatomic gas from 0$$^\circ$$ C to 50$$^\circ$$ C when no work is done is ___________. (R is the universal gas constant).
A
500 R
B
250 R
C
750 R
D
175 R
4
JEE Main 2021 (Online) 20th July Morning Shift
MCQ (Single Correct Answer)
+4
-1
Change Language
The entropy of any system is given by
$$S = {\alpha ^2}\beta \ln \left[ {{{\mu kR} \over {J{\beta ^2}}} + 3} \right]$$ where $$\alpha$$ and $$\beta$$ are the constants. $$\mu$$, J, k and R are no. of moles, mechanical equivalent of heat, Boltzmann constant and gas constant respectively.
[Take $$S = {{dQ} \over T}$$]
Choose the incorrect option from the following :
A
$$\alpha$$ and J have the same dimensions.
B
S and $$\alpha$$ have different dimensions
C
S, $$\beta$$, k and $$\mu$$R have the same dimensions
D
$$\alpha$$ and k have the same dimensions
JEE Main Subjects
EXAM MAP
Medical
NEETAIIMS
Graduate Aptitude Test in Engineering
GATE CSEGATE ECEGATE EEGATE MEGATE CEGATE PIGATE IN
Civil Services
UPSC Civil Service
Defence
NDA
Staff Selection Commission
SSC CGL Tier I
CBSE
Class 12