1
JEE Main 2022 (Online) 24th June Morning Shift
MCQ (Single Correct Answer)
+4
-1
Change Language

A resistance of 40 $$\Omega$$ is connected to a source of alternating current rated 220 V, 50 Hz. Find the time taken by the current to change from its maximum value to the rms value :

A
2.5 ms
B
1.25 ms
C
2.5 s
D
0.25 s
2
JEE Main 2022 (Online) 24th June Morning Shift
MCQ (Single Correct Answer)
+4
-1
Change Language

The equations of two waves are given by :

y1 = 5 sin 2$$\pi$$(x - vt) cm

y2 = 3 sin 2$$\pi$$(x $$-$$ vt + 1.5) cm

These waves are simultaneously passing through a string. The amplitude of the resulting wave is :

A
2 cm
B
4 cm
C
5.8 cm
D
8 cm
3
JEE Main 2022 (Online) 24th June Morning Shift
MCQ (Single Correct Answer)
+4
-1
Change Language

A plane electromagnetic wave travels in a medium of relative permeability 1.61 and relative permittivity 6.44. If magnitude of magnetic intensity is 4.5 $$\times$$ 10$$-$$2 Am$$-$$1 at a point, what will be the approximate magnitude of electric field intensity at that point?

(Given : Permeability of free space $$\mu$$0 = 4$$\pi$$ $$\times$$ 10$$-$$7 NA$$-$$2, speed of light in vacuum c = 3 $$\times$$ 108 ms$$-$$1)

A
16.96 Vm$$-$$1
B
2.25 $$\times$$ 10$$-$$2 Vm$$-$$1
C
8.48 Vm$$-$$1
D
6.75 $$\times$$ 106 Vm$$-$$1
4
JEE Main 2022 (Online) 24th June Morning Shift
MCQ (Single Correct Answer)
+4
-1
Change Language

Choose the correct option from the following options given below :

A
In the ground state of Rutherford's model electrons are in stable equilibrium. While in Thomson's model electrons always experience a net-force.
B
An atom has a nearly continuous mass distribution in a Rutherford's model but has a highly non-uniform mass distribution in Thomson's model.
C
A classical atom based on Rutherford's model is doomed to collapse.
D
The positively charged part of the atom possesses most of the mass in Rutherford's model but not in Thomson's model.
JEE Main Papers
2023
2021
EXAM MAP
Medical
NEET
Graduate Aptitude Test in Engineering
GATE CSEGATE ECEGATE EEGATE MEGATE CEGATE PIGATE IN
CBSE
Class 12