A coil of N turns and mean cross-sectional area A is rotating with uniform angular velocity ω about an axis at right angle to uniform magnetic field B. The induced emf in the coil will be
(a) NBAsinωt
(b) NBωsinωt
(c) NB/Asinωt
(d) NBAωsinωt
(a) NBAsinωt
(b) NBωsinωt
(c) NB/Asinωt
(d) NBAωsinωt
(d) NBAωsinωt
The magnetic flux linked with a coil is given by the equation Ø = 2t² + 2t + 4 weber. The magnitude of induced emf at time t=2s will be
(a) 16 V
(b) 10V
(c) 12V
(d) 8V
A coil of wire of certain radius has 500 turns and self inductance of 75 mH. The self inductance of a second similar coil of 600 turns will be
(a) 100 mH
(b) 150mH
(c) 108 mH
(d) 105mH
The magnetic flux linked with a coil is given by an equation Φ = 5t² + 2t + 3. The induced e.m.f. in the coil at the third second will be
(A) 32 units
(B) 54 units
(C) 40 units
(D) 65 units
A conducting rod of unit length moves with a velocity 10 m/s in a direction perpendicular to its length and perpendicular to a uniform magnetic field of magnitude 0.2 T. The emf induced between the ends of the rod is
(a) 4 V
(b) 2V
(c) 1V
(d) Zero
In a circuit with a coil of resistance 3Ω, the magnetic flux changes from 1.0 Wb to 10.0 Wb in 0.3 s. The charge that flows in the coil during this time is
(a) 2.0 C
(b) 3.0 C
(c) 4.0 C
(d) 1.0 C
Two currents loops are concentric and lie in the same plane. The current in the outer loop is anti clockwise and increasing with time. The induced current in the inner loop ,is
(a) Clockwise
(b) Zero
(c) Counter-clockwise
(d) None of these
A long solenoid has 2000 turns. When a current of 2 A flows through it, then the magnetic flux linked with each turn of the solenoid is 2 × 10⁻³ Wb. The self inductance of the solenoid is
(a) 1 H
(b) 2 H
(c) 3 H
(d) 4 H
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
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/\(d^2\)
Three charges each equal to 2 μC are placed at the corners of an equilateral triangle. If force between any two charges is 2F, then the net force on either will be:
A young’s double slit experiment uses a monochromatic source. The shape of interference fringes formed on a screen is :
a. Parabola
b. straight line
c. circle
d. Hyperbola
In Young’s double slit experiment, using sodium light (λ = 5898) , 92 fringes are seen. If given colour (λ= 5461) is used, how many fringes will be seen?
I. 67
II. 95
III. 99
IV. 84
The magnetic field at an outside point due to a long straight conductor carrying a constant current(I) is independent of
a) Material of the conductor
b) Radius of the conductor
c) Both (a) and (b)
d) Neither (a) nor (b)
What is the angle between the electric dipole moment and electric field strength due to it on the axial line?
(A) \(0^\circ\)
(B) \(90^\circ\)
(C) \(180^\circ\)
(D) None of these