Which charge configuration produces a uniform electric field?

(a)

point charge

(b)

uniformly charged infinite line

(c)

uniformly charged infinite plane

(d)

uniformly charged spherical shell

An electric field \(\vec { E } =10x\hat { i } \) exists in a certain region of space. Then the potential difference V = V_o – V_A, where V_o is the potential at the origin and V_A is the potential at x = 2 m is _____.

(a)

10 V

(b)

-20 V

(c)

+20 V

(d)

-10 V

Two wires of A and B with circular cross section made up of the same material with equal lengths. Suppose R_A = 3 R_B, then what is the ratio of radius of wire A to that of B?

(a)

3

(b)

\(\sqrt3\)

(c)

\(\frac{1}{\sqrt3}\)

(d)

\(\frac{1}{3}\)

In Joule’s heating law, when R and t are constant, if the H is taken along the y axis and I² along the x axis, the graph is ______.

(a)

straight line

(b)

parabola

(c)

circle

(d)

ellipse

Three wires of equal lengths are bent in the form of loops. One of the loops is circle, another is a semi-circle and the third one is a square. They are placed in a uniform magnetic field and same electric current is passed through them. Which of the following loop configuration will experience greater torque?

(a)

Circle

(b)

Semi-circle

(c)

Square

(d)

All of them

When the current changes from +2A to −2A in 0.05 s, an emf of 8 V is induced in a coil. The co-efficient of self-induction of the coil is

(a)

0.2H

(b)

0.4H

(c)

0.8H

(d)

0.1H

If the amplitude of the magnetic field is 3 x 10⁻⁶ T, then amplitude of the electric field for a electromagnetic waves is _____.

(a)

100 V m⁻¹

(b)

300 V m^-1

(c)

600 V m^-1

(d)

900 V m^-1

Which of the following is an electromagnetic wave?

(a)

α - rays

(b)

β - rays

(c)

\(\gamma\) - rays

(d)

all of them

Stars twinkle due to, ______.

(a)

reflection

(b)

total internal reflection

(c)

refraction

(d)

polarisation

If the mean wavelength of light from sun is taken as 550 nm and its mean power as 3.8 x 10²⁶ W, then the number of photons emitted per second from the sun is of the order of _____.

(a)

10⁴⁵

(b)

10⁴²

(c)

10⁵⁴

(d)

10⁵¹

Atomic number of H-like atom with ionization potential 122.4 V for n = 1 is _____.

(a)

1

(b)

2

(c)

3

(d)

4

The barrier potential of a silicon diode is approximately, ______.

(a)

0.7 V

(b)

0.3 V

(c)

2.0 V

(d)

2.2 V

The output transducer of the communication system converts the radio signal into ________.

(a)

Sound

(b)

Mechanical energy

(c)

Kinetic energy

(d)

None of the above

“Sky wax” is an application of nano product in the field of _____.

(a)

Medicine

(b)

Textile

(c)

Sports

(d)

Automotive industry

The gravitational waves were theoretically proposed by _____.

(a)

Conrad Rontgen

(b)

Marie Curie

(c)

Albert Einstein

(d)

Edward Purcell

Define ‘electric dipole’. Give the expression for the magnitiude of its electric dipole moment and the direction.

State Kirchhoff ’s voltage rule.

Define magnetic flux.

Give the principle of AC generator.

What is displacement current?

What is Snell’s window?

Define ‘Electric field’ and discuss its various aspects.

State and explain Kirchhoff ’s rules

What is tangent law? Discuss in detail.

Give the uses of Foucault current.

Write short notes on
(a) microwaves
(b) X - rays
(c) Radio waves
(d) Visible spectrum

Discuss the source of electromagnetic waves.

(i) In figure (a), calculate the electric flux through the closed areas A₁ and A₂.
(ii) In figure (b), calculate the electric flux through the cube.

For the given circuit find the value of I.

Write down the equation for a sinusoidal voltage of 50 Hz and its peak value is 20 V. Draw the corresponding voltage versus time graph.

A bicycle wheel with metal spokes of 1 m long rotates in Earth’s magnetic field. The plane of the wheel is perpendicular to the horizontal component of Earth’s field of 4×10⁻⁵T. If the emf induced across the spokes is 31.4 mV, calculate the rate of revolution of the wheel.

When does power factor of a series RLC circuit become maximum?