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
(a) 2 : 1
(b) 1 : 2
(c) 4 : 1
(d) 1 : 4
(a) 2 : 1
Two slits in Young’s double slit experiment have widths in the ratio 81:1. The ratio of the amplitudes of light waves is
(a) 3 :1
(b) 3 : 2
(c) 9 :1
(d) 6:1
The ratio of intensities at minima to the maxima in young’s double slit experiment is 9 : 25. Find the ratio of the widths of two slits.
(A) 16: 1
(B) 1: 16
(C) 4 : 1
(D) 1 : 4
A phase difference of 5π corresponds to a path difference (in terms of λ) of:
(a) 5λ
(b) 10λ.
(c) 5λ/2
(d) 2λ
The idea of secondary wavelets for the propagation of a wave was first given by
(a) Newton
(b) Huygens
(c) Maxwell
(d) Fresnel
When light suffers reflection at the interface between water and glass, the change of phase in the reflected wave is
(a) zero..
(b) π.
(c) π/2.
(d) 2π.
Wavefront is the locus of all points, where the particles of the medium vibrate with the same
(a) phase.
(b) amplitude.
(c) frequency.
(d) period.
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 potential energy of a charged parallel plate capacitor is \(U_0\). If a slab of dielectric constant K is inserted between the plates, then new potential energy will be
(a) \(U_0\)/K
(b) \(U_0\)K²
(c) \(U_0\)/K²
(d) \(U_0\)²
In a Wheatstone bridge, three resistors P,Q, R are connected in three arms in order and 4th arm of resistance, s, is formed by two resistors s1 and s2 connected in parallel. The condition for bridge to be balanced is, P/Q
Polaroid glasses is used in sun glasses because :
a. It reduces the light intensity to half on account of polarization
b. It is fashionable
c. It has good colour
d. It is cheaper
the magnitude of a charge q at the center of two equal and like charges Q so that the three charges are in equilibrium
A. Q
B. Q/2
C. Q/4
D. –Q/4
Unit of magnetic dipole moment is
a) ampere meter
b) ampere/meter⁻¹
c) ampere metre²
d) ampere/metre²
A capacitor of capacity C has reactance X. If capacitance and frequency become double then reactance will be
(a) 4X
(b) X/2
(c) X/4
(d) 2X
The angular resolution of a 10 cm diameter telescope at a wavelength of 5000 A is of the order of
(a) \(10^6\) rad
(b) \(10^{-2}\) rad
(c) \(10^{-4}\) rad
(d) \(10^{-6}\) rad