1
JEE Main 2020 (Online) 5th September Evening Slot
MCQ (Single Correct Answer)
+4
-1
Change Language
The correct match between the entries in column I and column II are :

I II
Radiation Wavelength
(a) Microwave (i) 100 m
(b) Gamma rays (ii) 10–15 m
(c) A.M. radio waves (iii) 10–10 m
(d) X-rays (iv) 10–3 m
A
(a)-(ii), (b)-(i), (c)-(iv), (d)-(iii)
B
(a)-(iv), (b)-(ii), (c)-(i), (d)-(iii)
C
(a)-(iii), (b)-(ii), (c)-(i), (d)-(iv)
D
(a)-(i), (b)-(iii), (c)-(iv), (d)-(ii)
2
JEE Main 2020 (Online) 5th September Morning Slot
MCQ (Single Correct Answer)
+4
-1
Change Language
An electron is constrained to move along the y-axis with a speed of 0.1 c (c is the speed of light) in the presence of electromagnetic wave, whose electric field is
$$\overrightarrow E = 30\widehat j\sin \left( {1.5 \times {{10}^7}t - 5 \times {{10}^{ - 2}}x} \right)$$ V/m.
The maximum magnetic force experienced by the electron will be :
(given c = 3 $$ \times $$ 108 ms–1 and electron charge = 1.6 $$ \times $$ 10–19 C)
A
4.8 $$ \times $$ 10–19 N
B
2.4 $$ \times $$ 10–18 N
C
3.2 $$ \times $$ 10–18 N
D
1.6 $$ \times $$ 10–18 N
3
JEE Main 2020 (Online) 4th September Evening Slot
MCQ (Single Correct Answer)
+4
-1
Change Language
The electric field of a plane electromagnetic wave is given by
$$\overrightarrow E = {E_0}\left( {\widehat x + \widehat y} \right)\sin \left( {kz - \omega t} \right)$$
Its magnetic field will be given by :
A
$${{{E_0}} \over c}\left( {\widehat x + \widehat y} \right)\sin \left( {kz - \omega t} \right)$$
B
$${{{E_0}} \over c}\left( {\widehat x - \widehat y} \right)\sin \left( {kz - \omega t} \right)$$
C
$${{{E_0}} \over c}\left( {\widehat x - \widehat y} \right)\cos \left( {kz - \omega t} \right)$$
D
$${{{E_0}} \over c}\left( { - \widehat x + \widehat y} \right)\sin \left( {kz - \omega t} \right)$$
4
JEE Main 2020 (Online) 4th September Morning Slot
MCQ (Single Correct Answer)
+4
-1
Change Language
Choose the correct option relating wave lengths of different parts of electromagnetic wave spectrum:
A
$$\lambda $$radio waves > $$\lambda $$micro waves > $$\lambda $$visible > $$\lambda $$x-rays
B
$$\lambda $$visible > $$\lambda $$x-rays > $$\lambda $$radio waves > $$\lambda $$micro waves
C
$$\lambda $$visible < $$\lambda $$micro waves < $$\lambda $$radio waves < $$\lambda $$x-rays
D
$$\lambda $$x-rays < $$\lambda $$micro waves < $$\lambda $$radio waves < $$\lambda $$visible
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