1
COMEDK 2025 Evening Shift
MCQ (Single Correct Answer)
+1
-0
The stopping potential when a metal surface is illuminated by light of wavelength $\lambda$ is 15 V . The stopping potential when the same surface is illuminated by light of wavelength $4 \lambda$ is 3 V . The ratio of threshold wavelength to the initial incident wavelength $\lambda$ is:
A
$1: 16$
B
$1: 15$
C
$16: 1$
D
$15: 1$
2
COMEDK 2025 Evening Shift
MCQ (Single Correct Answer)
+1
-0
A wire of negligible mass having uniform area of cross section ' A ' and young modulus ' Y ' is used to suspend a point mass ' m '. The point mass executes simple harmonic motion in a vertical plane with a period ' T ', then the length of the wire is :
A
$L=\frac{T Y^2 A}{4 \pi^2 m}$
B
$L=\frac{T^2 Y A}{4 \pi m^2}$
C
$L=\frac{T Y^2 A}{4 \pi m^2}$
D
$L=\frac{T^2 Y A}{4 \pi^2 m}$
3
COMEDK 2025 Evening Shift
MCQ (Single Correct Answer)
+1
-0
Applying a constant torque the speed of a flywheel is increased from 1800 rpm to 2400 rpm in 10 seconds. The number of revolutions made by the flywheel during this time is:
A
350
B
900
C
700
D
2100
4
COMEDK 2025 Evening Shift
MCQ (Single Correct Answer)
+1
-0
A short bar magnet placed with its axis at $45^{\circ}$ with an external field of $400 \times 10^{-4} \mathrm{~T}$ experiences a torque of 0.024 Nm . If a solenoid of cross-sectional area $10^{-4} \mathrm{~m}^2$ and 500 turns replaces the short bar magnet such that they have the same magnetic moment, then the current flowing through the solenoid is:
A
$2 \sqrt{2} \mathrm{~A}$
B
$5 \sqrt{2} \mathrm{~A}$
C
$12 \sqrt{2} \mathrm{~A}$
D
$4 \sqrt{2} \mathrm{~A}$
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