1
JEE Main 2019 (Online) 9th April Morning Slot
MCQ (Single Correct Answer)
+4
-1
Change Language
An HCl molecule has rotational, translational and vibrational motions. If the rms velocity of HCl molecules in its gaseous phase is $$\overline v $$ , m is its mass and kB is Boltzmann constant, then its temperature will be :
A
$${{m{{\overline v }^2}} \over {5{k_B}}}$$
B
$${{m{{\overline v }^2}} \over {6{k_B}}}$$
C
$${{m{{\overline v }^2}} \over {7{k_B}}}$$
D
$${{m{{\overline v }^2}} \over {3{k_B}}}$$
2
JEE Main 2019 (Online) 9th April Morning Slot
MCQ (Single Correct Answer)
+4
-1
Change Language
The following bodies are made to roll up (without slipping) the same inclined plane from a horizontal plane. : (i) a ring of radius R, (ii) a solid cylinder of radius R/2 and (iii) a solid sphere of radius R/4 . If in each case, the speed of the centre of mass at the bottom of the incline is same, the ratio of the maximum heights they climb is :
A
20 : 15 : 14
B
4 : 3 : 2
C
2 : 3 : 4
D
10 : 15 : 7
3
JEE Main 2019 (Online) 9th April Morning Slot
MCQ (Single Correct Answer)
+4
-1
Change Language
A solid sphere of mass 'M' and radius 'a' is surrounded by a uniform concentric spherical shell of thickness 2a and mass 2M. The gravitational field at distance '3a' from the centre will be :
A
$${{GM} \over {3{a^2}}}$$
B
$${{2GM} \over {9{a^2}}}$$
C
$${{GM} \over {9{a^2}}}$$
D
$${{2GM} \over {3{a^2}}}$$
4
JEE Main 2019 (Online) 9th April Morning Slot
MCQ (Single Correct Answer)
+4
-1
Change Language
A system of three charges are placed as shown in the figure :

JEE Main 2019 (Online) 9th April Morning Slot Physics - Electrostatics Question 216 English If D >> d, the potential energy of the system is best given by :
A
$${1 \over {4\pi {\varepsilon _0}}}\left[ { {{{q^2}} \over d} + {{qQd} \over {{D^2}}}} \right]$$
B
$${1 \over {4\pi {\varepsilon _0}}}\left[ { - {{{q^2}} \over d} - {{qQd} \over {2{D^2}}}} \right]$$
C
$${1 \over {4\pi {\varepsilon _0}}}\left[ { - {{{q^2}} \over d} - {{qQd} \over {{D^2}}}} \right]$$
D
$${1 \over {4\pi {\varepsilon _0}}}\left[ { - {{{q^2}} \over d} + {2{qQd} \over {{D^2}}}} \right]$$

JEE Main Papers

All year-wise previous year question papers

2023
2021