1
MHT CET 2021 20th September Morning Shift
MCQ (Single Correct Answer)
+1
-0

When a d.c. voltage of $$200 \mathrm{~V}$$ is applied to a coil of self-inductance $$\left(\frac{2 \sqrt{3}}{\pi}\right) \mathrm{H}$$, a current of $$1 \mathrm{~A}$$ flows through it. But by replacing d.c. source with a.c. source of $$200 \mathrm{~V}$$, the current in the coil is reduced to $$0.5 \mathrm{~A}$$. Then the frequency of a.c. supply is

A
100 Hz
B
60 Hz
C
75 Hz
D
50 Hz
2
MHT CET 2021 20th September Morning Shift
MCQ (Single Correct Answer)
+1
-0

When light of wavelength '$$\lambda$$' is incident on a photosensitive surface, photons of power 'P' are emitted. The number of photon 'n' emitted in time 't' is [h = Planck's constant, c = velocity of light in vacuum]

A
$$\mathrm{\frac{hc}{p\lambda t}}$$
B
$$\mathrm{\frac{P\lambda}{htc}}$$
C
$$\mathrm{\frac{P\lambda t}{hc}}$$
D
$$\mathrm{\frac{hP}{\lambda tc}}$$
3
MHT CET 2021 20th September Morning Shift
MCQ (Single Correct Answer)
+1
-0

Air is pushed in a soap bubble to increase its radius from 'R' to '2R'. In this case, the pressure inside the bubble

A
does not change
B
decrease
C
becomes zero
D
increases
4
MHT CET 2021 20th September Morning Shift
MCQ (Single Correct Answer)
+1
-0

The equation of wave is given by $$\mathrm{y}=10 \sin \left(\frac{2 \pi \mathrm{t}}{30}+\alpha\right)$$. If the displacement is $$5 \mathrm{~cm}$$ at $$\mathrm{t}=0$$, then the total phase at $$\mathrm{t}=7.5 \mathrm{~s}$$ will be

$$\left[\sin 30^{\circ}=\cos 60^{\circ}=\frac{1}{2}, \cos 30^{\circ}=\sin 60^{\circ}=\frac{\sqrt{3}}{2}\right] $$

A
$$\frac{\pi}{3} \mathrm{rad}$$
B
$$\frac{\pi}{2} \mathrm{rad}$$
C
$$\frac{2 \pi}{5} \mathrm{rad}$$
D
$$\frac{2 \pi}{3} \mathrm{rad}$$
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