If the charge on each plate of a capacitor of 60μF is 3x\(10^{-8}\)C, then energy stored in the capacitor will be
(a) 2.5x\(10^{-15}\)J
(b) 1.5x\(10^{-14}\)J
(c) 3.5x\(10^{-13}\)J
(d) 7.5x\(10^{-12}\)J
(a) 2.5x\(10^{-15}\)J
(b) 1.5x\(10^{-14}\)J
(c) 3.5x\(10^{-13}\)J
(d) 7.5x\(10^{-12}\)J
(d) 7.5x\(10^{-12}\)J
In which of the following forms is the energy stored in a capacitor?
(a) Charge
(b) Potential
(c) Capacitance
(d) Electric field
An electron initially at rest is accelerated through a potential difference of one volt. The energy gained by electron is:
(a) 1 J
(b) 1.6 × \(10^{-19}\) J
(c) \(10^{-19}\) J
(d) None of these
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
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 capacitance of a capacitor will decrease if we introduce a slab of:
(a) copper
(b) aluminium
(c) zinc
(d) None of these
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
A capacitor is connected across a battery and the plate separation of capacitor is increased without removing the battery, then:
(a) capacitance will increase
(b) charge stored will increase
(c) energy stored will decrease
(d) potential difference will increase
Let \(ε_0\) denote the dimensional formula of the permittivity of vacuum. If M=mass, L=length, T=time and
I=electric current, then
(A) [M⁻¹L⁻³T²I]
(B) [M⁻¹L⁻³T⁴I²]
(C) [M⁻¹L²T⁻¹I⁻²]
(D) [M⁻¹L²T⁻¹I]
What happens if one of the slits, say S1 in Young’s double , slit experiment-is covered with a glass plate which absorbs half the intensity of light from it?
(a) The bright fringes become less-bright and the dark fringes have a finite light intensity
(b) The bright fringes become brighter and the dark fringes become darker
(c) The fringe width decreases
(d) No fringes will be observed
The phenomena which is not explained by Huygen’s construction of wavefront
(a) reflection
(b) diffraction
(c) refraction
(d) origin of spectra
The fringe width (β) of a diffraction pattern and the slit width d are related as:
(a) β ∝ d
(b) β ∝1/d
(c) β ∝ √d
(d) β ∝ 1/\(d^2\)
A transformer having efficiency of 90% is working on 200 V and 3 kW power supply. If the current in the secondary coil is 6 A, the voltage across the secondary coil and the current in the primary coil respectively are
(a) 300 V, 15 A
(b) 450 V, 15 A
(c) 450 V, 13.5 A
(d) 600 V, 5 A
What happen when we use white light in Young’s double slit experiment.
(A) No interference pattern will form
(B) white fringes will form
(C) Central bright fringe will be white
(D) Central fringe will be coloured