An electric charge of 425 f μC is removed from a fully charged capacitor of capacitance 8.5μF. Its potential will be lowered by:
(a) 75 V
(b) 100 V
(c) 85 V
(d) 50 V
(a) 75 V
(b) 100 V
(c) 85 V
(d) 50 V
(b) 100 V
Minimum number of capacitor of 2μF each required to obtain a capacitance of 5μF will be:
(a) 4
(b) 3
(c) 5
(d) 6
The electric potential due to point charge 3 nC at distance of 9 cm is
(a) 270 v
(b) 3 v
(c) 300 v
(d) 30 v
The capacitance of earth, viewed as a spherical conductor of radius 6408 km is:
(a) 1420 μF
(b) 712 μF
(c) 680 μF
(d) 540 μF
The electrostatic potential energy between proton and electron separated by a distance of 1 Å is
(a) 13.6eV
(b) 27.2eV
(c) -14.4eV
(d) 1.44eV
The amount of work required to increase the distance between -6µC and 4µC from 6 cm to 18 cm will be :
(a) 1.8 J
(b) 2.4 J
(c) 1.8 µJ
(d) 2.4 µJ
Electric potential at a distance r from the point charge is proportional to
1. \(r^2\)
2. r-1
3. r0
4. r+1
According to Huygens, medium through which light travel is
(A) vacuum only
(B) luminiferous either
(C) liquid only
(D) solid only
A screen is placed 50m from a single slit, which is illuminated with 6000Å light. If the distancebetween the first and third minima in the diffraction pattern is 3.00mm, what is the width of the slit ?
i. 200 µm
ii. 300 µm
iii. 250 µm
iv. 350 µm
A solenoid has 1000 turns per metre length. If a current of 5A is flowing through it, then magnetic field inside the solenoid is-
The wavefront due to a source situated at infinity is
(a) spherical
(b) cylindrical
(c) planar
(d) circular
A glass rod acquires charge by rubbing it with silk cloth. The charge on glass rod is due to :
(A) Friction
(B) Conduction
(C) Induction
(D) Radiation
A current loop placed in a magnetic field behaves like a
a) Magnetic substance
b) Magnetic pole
c) Magnetic dipole
d) all true
The colours of a soap bubble seen in sunlight is due to ......... And colour due to a prism appears due to .............
Choose the right answers respectively
(A) Interference of light; refraction of light
(B) Dispersion of light; total internal reflection of light
(C) Interference of light; polarization of light
(D) Interference of light; dispersion of light