A small signal voltage V(t) = V₀ sin(ωt) is applied across an ideal capacitor C
(a) Current I(t) is in phase with voltage V(t).
(b) Current I(t) leads voltage V(t) by 180°.
(c) Current I(t), lags voltage V(t) by 90°.
(d) Over a full cycle the capacitor C does not consume any energy from the voltage source
(a) Current I(t) is in phase with voltage V(t).
(b) Current I(t) leads voltage V(t) by 180°.
(c) Current I(t), lags voltage V(t) by 90°.
(d) Over a full cycle the capacitor C does not consume any energy from the voltage source
(d) Over a full cycle the capacitor C does not consume any energy from the voltage source
An ac voltage V = V₀ sin ωt is applied to a pure inductor L. Obtain an expression for the current in the circuit. Prove that the average power supplied to an inductor over one complete cycle is zero.
A source of ac voltage V = V₀ sin ωt, is connected across a pure inductor of inductance L. Derive the expressions for the instantaneous current in the circuit. Show that average power dissipated in the circuit is zero.
For an ideal conductor, connected across a sinusoidal ac voltage source. State which one of the following quantity is zero :
(i) Instantaneous power
(ii) Average power over full cycle of the ac voltage source.
A source of ac voltage V = V₀ sin ωt is connected to a series combination of a resistor ‘R’ and a capacitor ‘C’. Draw the phasor diagram and use it to obtain the expression for
(i) impedance of the circuit and
(ii) phase angle.
A sinusoidal voltage of peak value 10 V is applied to a series LCR circuit in which resistance,capacitance and inductance have values of 10 Ω,1 µF and 1 H respectively. Find
(i) the peak voltage across the inductor at resonance
(ii) quality factor of the circuit.
A voltage V = V₀ sin ωt is applied to a series LCR circuit. Derive the expression for the average power dissipate over a cycle.Under what conditions is
(i) no power dissipated even though the current flows through the circuit,
(ii)maximum power dissipated in the circuit ?
A 200 mH (pure) inductor and a 5 µF (pure) capacitor are connected one by one, across a sinusoidal ac voltage source of V = [70.7sin (1000t)] voltage. Obtain the expression for the current in each case.
The parameter of light wave which remain same after refraction
(A) speed
(B) frequency
(C) wavelength
(D) none of these
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
Ratio of intensities of two waves are given by 4 :1. Then the ratio of the amplitudes of the two waves.
(a) 2 : 1
(b) 1 : 2
(c) 4 : 1
(d) 1 : 4
Two waves having intensities in the ratio of 9:1 produce interference. The ratio of the maximum to the minimum intensity is
I. 9:1
II. 4:1
III. 1:2
IV. 1:3
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
what is the angle between an electric dipole moment and then electric field strength due to it on its equatorial line?
(A) \(0^\circ\)
(B) \(90^\circ\)
(C) \(180^\circ\)
(D) None of these
A wire of resistance 0.5 Ωm⁻¹ is bent into a circle of radius 1m. The same wire is connected across a diameter AB as shown in the fig. The equivalent resistance is
(a) Π ohm
(b) Π (Π + 2) ohm
(c) Π/( Π + 4) ohm
(d) (Π + 1) ohm