1
JEE Main 2021 (Online) 26th February Morning Shift
MCQ (Single Correct Answer)
+4
-1
Change Language
In a typical combustion engine the workdone by a gas molecule is given by $$W = {\alpha ^2}\beta {e^{{{ - \beta {x^2}} \over {kT}}}}$$, where x is the displacement, k is the Boltzmann constant and T is the temperature. If $$\alpha$$ and $$\beta$$ are constants, dimensions of $$\alpha$$ will be :
A
$$[{M^0}L{T^0}]$$
B
$$[ML{T^{ - 1}}]$$
C
$$[ML{T^{ - 2}}]$$
D
$$[{M^2}L{T^{ - 2}}]$$
2
JEE Main 2021 (Online) 25th February Evening Shift
MCQ (Single Correct Answer)
+4
-1
Change Language
If e is the electronic charge, c is the speed of light in free space and h is Planck's constant, the quantity $${1 \over {4\pi {\varepsilon _0}}}{{|e{|^2}} \over {hc}}$$ has dimensions of :
A
$$[ML{T^{ - 1}}]$$
B
$$[ML{T^0}]$$
C
$$[{M^0}{L^0}{T^0}]$$
D
$$[L{C^{ - 1}}]$$
3
JEE Main 2021 (Online) 25th February Morning Shift
MCQ (Single Correct Answer)
+4
-1
Change Language
Match List - I with List - II :

List I List II
(a) h (Planck's constant) (i) $$[ML{T^{ - 1}}]$$
(b) E (kinetic energy) (ii) $$[M{L^2}{T^{ - 1}}]$$
(c) V (electric potential) (iii) $$[M{L^2}{T^{ - 2}}]$$
(d) P (linear momentum) (iv) $$[M{L^2}{I^{ - 1}}{T^{ - 3}}]$$


Choose the correct answer from the options given below :
A
(a) $$ \to $$ (ii), (b) $$ \to $$ (iii), (c) $$ \to $$ (iv), (d) $$ \to $$ (i)
B
(a) $$ \to $$ (i), (b) $$ \to $$ (ii), (c) $$ \to $$ (iv), (d) $$ \to $$ (iii)
C
(a) $$ \to $$ (iii), (b) $$ \to $$ (ii), (c) $$ \to $$ (iv), (d) $$ \to $$ (i)
D
(a) $$ \to $$ (iii), (b) $$ \to $$ (iv), (c) $$ \to $$ (ii), (d) $$ \to $$ (i)
4
JEE Main 2021 (Online) 25th February Morning Shift
MCQ (Single Correct Answer)
+4
-1
Change Language
The pitch of the screw gauge is 1 mm and there are 100 divisions on the circular scale. When nothing is put in between the jaws, the zero of the circular scale lies 8 divisions below the reference line. When a wire is placed between the jaws, the first linear scale division is clearly visible while 72nd division on circular scale coincides with the reference line. The radius of the wire is :
A
1.80 mm
B
0.90 mm
C
0.82 mm
D
1.64 mm
JEE Main Subjects
EXAM MAP
Medical
NEET
Graduate Aptitude Test in Engineering
GATE CSEGATE ECEGATE EEGATE MEGATE CEGATE PIGATE IN
Civil Services
UPSC Civil Service
CBSE
Class 12