1
JEE Main 2021 (Online) 17th March Morning Shift
MCQ (Single Correct Answer)
+4
-1
Change Language
An electron of mass m and a photon have same energy E. The ratio of wavelength of electron to that of photon is : (c being the velocity of light)
A
$${1 \over c}{\left( {{{2m} \over E}} \right)^{1/2}}$$
B
$${1 \over c}{\left( {{E \over {2m}}} \right)^{1/2}}$$
C
$${\left( {{E \over {2m}}} \right)^{1/2}}$$
D
$$c{(2mE)^{1/2}}$$
2
JEE Main 2021 (Online) 16th March Evening Shift
MCQ (Single Correct Answer)
+4
-1
Change Language
The de-Broglie wavelength associated with an electron and a proton were calculated by accelerating them through same potential of 100 V. What should nearly be the ratio of their wavelengths? (mp = 1.00727u me = 0.00055u)
A
41.4 : 1
B
(1860)2 : 1
C
1860 : 1
D
43 : 1
3
JEE Main 2021 (Online) 16th March Morning Shift
MCQ (Single Correct Answer)
+4
-1
Change Language
The stopping potential in the context of photoelectric effect depends on the following property of incident electromagnetic radiation :
A
Phase
B
Frequency
C
Amnplitude
D
Intensity
4
JEE Main 2021 (Online) 26th February Evening Shift
MCQ (Single Correct Answer)
+4
-1
Change Language
The recoil speed of a hydrogen atom after it emits a photon in going from n = 5 state to n = 1 state will be :
A
4.34 m/s
B
2.19 m/s
C
3.25 m/s
D
4.17 m/s
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