Physics Mock Te...

The magnetic effect of current was discovered by

The wavelength of photon is 0.01Å. If h be the Plank's constant, its momentum will be - 

The focal length of a convergent lens is R. Now if the lens is dipped into the water of refractive index 1.33, then the focal length of the lens will be (refractive index of the material of lens = 1.5):

The refractive index for a glass is 1.62. The sine of the critical angle for total internal refection at a glass-air interface is: 

The magnetic moment (m) of a current loop = _________. ('I' is the current in the loop and 'A' is the area of the rectangular loop)

The Wheatstone’s bridge is said to be balanced, when:

(i) Vd = Va

(ii) Zero flow current through galvanometer.

The frequency of incident photon is reduced in a photoelectric emission process then the stopping potential will-

Find the potential energy of an electric dipole of dipole moment 12 C m which is placed in an electric field of magnitude 6 N/C. The angle between dipole and the electric field is 60°

The coils of a step-down transformer have 500 turns and 5000 turns. In the primary coil, a current of 4 A at 2200 volts is sent. The value of the current in the secondary coil will be

If the drift velocity of electrons is 6.7 × 10-5 ms-1, calculate the electron mobility when an electric field of 3.35 Vm^-1 is applied across a conductor.

What should be the properties of the core of electromagnets?

Two plates are at potentials -10 V and +30 V. If the separation between the plates is 2 cm then find the electric field between them.

Carbon resistors are made in —

The end product of the decay of ₉₀Th²³² is ₈₂Pb²⁰⁸. The number of α and β-particles emitted are respectively 

Wavelength of first line of Balmer series of Hydrogen is 6561 Å then the wavelength of second line of Balmer series will be :

Which of the following graphs correctly represents the variation of heat energy (U) produced in a metallic conductor in a given time as a function of potential difference (V) across the conductor?

Two long current-carrying wires of equal length are placed parallel to each other and separated by a small distance, if the length of both the wires is doubled then the force per unit length on the wires will:

Two charges +q and -q are placed at points A(a,0) and B(-a,0) on the x-axis. The potential due to this system of charges on point P(r, θ) with position vector \(\vec r\)will be? Given that q, a are positive constants and r >> a.

The refractive index of core and cladding for a step index fibre is 1.52 and 1.41 respectively. Its critical angle at core cladding boundary is:

A 4μF capacitor is charged to 400 volts and then its plates are joined through a resistance of 1 kΩ. The heat produced in the resistance is:

How many α and β particles are emitted when \(Th_{90}^{232}\) changes to \(P_{82}^{208}\) ?

A) 

B) 

C) 

In the following combination of logic gates, the outputs of A, B and C are respectively

What is the peak-to-peak voltage of a 2 V_RMS sine wave ?

The resolving power of a telescope is R. If the wavelength of light used is tripled then the resolving power will become;

In a coil of area 20 cm² and 10 turns with a magnetic field directed perpendicular to the plane and is changing at the rate of 10⁷ gauss/sec. The resistance of the coil is 20 ohm. The current in the coil will be:

A single-phase transformer has 1000 turns on the primary and 400 turns on the secondary side. Find the transformer ratio of the transformer?

A full wave rectifier is operating from 50 Hz mains, the fundamental frequency in the ripple will be:

The __________ diode is designed to operate under reverse bias in the breakdown region and used as a voltage regulator.

Which of the following electromagnetic waves have the maximum wavelength:

In an isosceles triangle, the side AB and BC are equal. If the charge at A and C are fixed and the charge at B can move, then how the charges +q, +q, and -q will be placed on the vertex, such that the charge at B will move perpendicular to the side AC?

In the Young’s double slit  experiment, the width ratio of slit is 1 : 4 . Find the ratio of amplitude of light waves coming from them.

If we increase the distance between the plates of a parallel plate capacitor by two times, what will be the change in potential difference between the plates?

In order to investigate the internal atomic structure of crystals, we make use of:

If the radius of the circular current-carrying coil is increased, then what will be the impact on magnetic induction/magnetic field at the centre of a circular coil

Find the equivalent resistance:

The angle of dip at a certain location is 45^∘.  Then the relationship between horizontal component of Earth's magnetic field H and total intensity of Earth's magnetic field I is-

10 cells are connected in parallel with the internal resistance of 1 Ω and 1.5 Volts. the total voltage and total resistance is ______

Two infinite plane parallel sheets having surface charge density +σ and –σ are kept parallel to each other at a small separation distance d. The electric field at any point in the region between the plates is

The number of free electrons 'n' in an intrinsic semiconductor is proportional to

If an alternating current is represented by i = 10 sin 314 t, where t is in seconds, then its frequency is around:

If the refractive index of water for red light is √3. Then find the Brewster angle for the air-water surface for a red light.

Which of the following optical phenomena CANNOT convert unpolarized light to light to plane polarized light?

The total equivalent capacitance of the series parallel combination of capacitors across A and B shown in figure is

If 2 kg of a substance is fully converted into energy, how much energy energy is produced

An astronomical telescope is focused on a distant star. If the distance between the objective lens and the eye piece is 2.5 m and the power of eye piece is 4D:

What will be the magnetic dipole moment at the center, if a straight copper wire is bent into a circular loops of 50 turns with constant current 6 A and radius of 2 cm

If 5.0 μC charge is placed at the center of a Gaussian surface in the form of a cube. The electric flux through any one face of the cube is: 

A current of 1.0 A is drawn by a filament of an electric bulb for 10 minutes. The amount of electric charge that flows through the circuit is

Two coherent light beams of wavelength λ are superimposed at a point. If the resultant intensity at that point is zero, then the possible path difference between the two waves at that point is:

The following figure represents