A parallel plate capacitor stores a charge Q at a voltage V. Suppose the area of the parallel plate capacitor and the distance between the plates are each doubled then which is the quantity that will change?

(a)

Capacitance

(b)

Charge

(c)

Voltage

(d)

Energy density

The internal resistance of a 2.1 V cell which gives a current of 0.2 A through a resistance of 10 Ω is ______.

(a)

0.2 Ω

(b)

0.5 Ω

(c)

0.8 Ω

(d)

1.0 Ω

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

A simple pendulum with charged bob is oscillating with time period T and lets θ be the angular displacement. If the uniform magnetic field switched ON in a direction perpendicular to the plane of oscillation then ___________.

(a)

time period will decrease but θ will remain constant

(b)

time period remain constant but θ will decrease

(c)

both T and θ will remain the same

(d)

both T and θ will decrease

In a transformer, the number of turns in the primary and the secondary are 410 and 1230 respectively. If the current in primary is 6A, then that in the secondary coil is

(a)

2 A

(b)

18 A

(c)

12 A

(d)

1 A

Which of the following electromagnetic radiations is used for viewing objects through fog 

(a)

microwave

(b)

gamma rays

(c)

X- rays

(d)

infrared

Which of the following is NOT true for electromagnetic waves?

(a)

it transport energy

(b)

it transport momentum

(c)

it transport angular momentum

(d)

in vacuum, it travels with different speeds which depend on their frequency

An air bubble in glass slab of refractive index 1.5 (near normal incidence) is 5 cm deep when viewed from one surface and 3 cm deep when viewed from the opposite face. The thickness of the slab is ______.

(a)

8 cm

(b)

10 cm

(c)

12 cm

(d)

16 cm

A ray of light strikes a glass plate at an angle 60^o. If the reflected and refracted rays are perpendicular to each other, the refractive index of the glass is, _____.

(a)

\(\sqrt3\)

(b)

\(\frac{3}{2}\)

(c)

\(\sqrt{\frac{3}{2}}\)

(d)

2

In an electron microscope, the electrons are accelerated by a voltage of 14 kV. If the voltage is changed to 224 kV, then the de Broglie wavelength associated with the electrons would _____.

(a)

increase by 2 times

(b)

decrease by 2 times

(c)

decrease by 4 times

(d)

increase by 4 times

Two radiations with photon energies 0.9 eV and 3.3 eV respectively are falling on a metallic surface successively. If the work function of the metal is 0.6 eV, then the ratio of maximum speeds of emitted electrons in the two cases will be _____.

(a)

1:4

(b)

1:3

(c)

1:1

(d)

1:9

The ratio between the radius of first three orbits of hydrogen atom is _____.

(a)

1:2:3

(b)

2:4:6

(c)

1:4:9

(d)

1:3:5

In J.J. Thomson e/m experiment, electrons are accelerated through 2.6 kV enter the region of crossed electric field and magnetic field of strength 3.0 x 10⁴ Vm^-1 and 1.0 x 10^-3 T, respectively, and pass through it and undeflected, then the specific charge is _____.

(a)

1.6 × 10¹⁰ C kg^–1

(b)

1.7 × 10¹¹ Ckg^–1

(c)

1.5 × 10¹¹ Ckg^–1

(d)

1.8 × 10¹¹ Ckg^–1

The nucleus is approximately spherical in shape. Then the surface area of nucleus having mass number A varies as _____.

(a)

A^2/3

(b)

A^4/3

(c)

A^1/3

(d)

A^5/3

If a positive half-wave rectified voltage is fed to a load resistor, for which part of a cycle there will be current flow through the load?

(a)

0⁰–90⁰

(b)

90⁰–180⁰

(c)

0⁰–180⁰

(d)

0⁰–360⁰

The principle based on which a solar cell operates is______.

(a)

Diffusion

(b)

Recombination

(c)

Photovoltaic action

(d)

Carrier flow

If the input to the NOT gate is A = 1011, its output is ______.

(a)

0100

(b)

1000

(c)

1100

(d)

0011

The variation of frequency of carrier wave with respect to the amplitude of the modulating signal is called ______.

(a)

Amplitude modulation

(b)

Frequency modulation

(c)

Phase modulation

(d)

Pulse width modulation

Which one of the following is the natural nanomaterial.

(a)

Peacock feather

(b)

Peacock beak

(c)

Grain of sand

(d)

Skin of the Whale

The alloys used for muscle wires in Robots are _____.

(a)

Shape memory alloys

(b)

Gold copper alloys

(c)

Gold silver alloys

(d)

Two dimensional alloys