List of top Physics Questions

A 15.7mW laser beam has a diameter of 4mm. If the amplitude of the associated magnetic field is expressed as \(\frac{𝐴}{\sqrt{ε_0𝑐^3}}\) , the value of A is: (𝜀₀ is the free space permittivity and 𝑐 is the speed of light)

Linearly polarized light (free space wavelength 𝜆₀= 600nm) is incident normally on a retarding plate (𝑛_𝑒-𝑛_𝑜 = 0.05 at 𝜆₀= 600nm). The emergent light is observed to be linearly polarized, irrespective of the angle between the direction of polarization and the optic axis of the plate. The minimum thickness (in µm) of the plate is:

In a Newton’s rings experiment (using light of free space wavelength 580nm), there is an air gap of height d between the glass plate and a plano-convex lens (see figure). The central fringe is observed to be bright.

The least possible value of d (in nm) is:

Given that the rest mass of electron is 0.511MeV/c ² , the speed (in units of c) of an electron with kinetic energy 5.11MeV is closest to:

The ultraviolet catastrophe in the classical (Rayleigh-Jeans) theory of cavity radiation is attributed to the assumption that

The roots of the polynomial, 𝑓(𝑧)=𝑧 ⁴-8𝑧 ³+27𝑧 ²-38𝑧+26, are 𝑧₁, 𝑧₂, 𝑧₃,& 𝑧₄, where 𝑧 is a complex variable. Which of the following statements is correct?

Consider the following logic circuit.

The output Y is LOW when:

The number of atoms in the basis of a primitive cell of hexagonal closed packed structure is:

A crystal plane of a lattice intercepts the principal axes \(\overrightarrow𝑎_1, \overrightarrow𝑎_2,\) and  \(\overrightarrow{a_3}\) at 3𝑎₁, 4𝑎₂, and 2𝑎₃, respectively. The Miller indices of the plane are:

Which of the following types of motion may be represented by the trajectory,
𝑦(𝑥)=𝑎𝑥 ²+𝑏𝑥+𝑐 ? 
(Here a, b, and c are constants; x, y are the position coordinates)

A particle moving along the x-axis approaches 𝑥=0 from 𝑥 =−∞ with a total energy E. It is subjected to a potential 𝑉(𝑥). For time 𝑡→∞, the probability density P(x) of the particle is schematically shown in the figure.

The correct option for the potential 𝑉(𝑥) is:

The magnitudes of spin magnetic moments of electron, proton and neutron are μ_e, μ_p and μ_n, respectively. Then

The sum of three binary numbers, 10110.10, 11010.01, and 10101.11, in decimal system is:

The total number of Na and Cl ions per unit cell of the NaCl crystal is:

Two resistors 2 Ω and 4 Ω are combined in parallel. If this combination is connected to a battery of 16 𝑉, the maximum current that can be drawn from the battery is ________ 𝐴 (rounded off to the nearest integer).

A ball is released from a height of \(1\) \(m\) on a fixed smooth hemispherical surface as shown. Find its velocity when it is at a height of \(0.5\) \(m\) from ground. (take \(g\) = \(10\;m / s^2\))

Force on a particle moving in a straight line is given by \( F = 6t^2\hat i - 3t\hat j\) and velocity is \(v = 3t^2\hat i + 6t\hat j\) . Find power at \(t = 2\).

In the diagram shown, the Zener diode has a reverse breakdown voltage \( V_z \). The current through the load resistance \( R_L \) is \( I_L \). The current through the Zener diode is

A solid cube of mass \( m \) at a temperature \( \theta_0 \) is heated at a constant rate. It becomes liquid at temperature \( \theta_1 \), and vapor at temperature \( \theta_2 \). Let \( s_1 \) and \( s_2 \) be specific heats in its solid and liquid states respectively. If \( L \) and \( L_v \) are latent heats of fusion and vaporization respectively, then the minimum heat energy supplied to the cube until it vaporises is

One mole of an ideal monatomic gas is taken round the cyclic process \( MNOM \). The work done by the gas is

A body of mass 1 kg is suspended by a weightless string which passes over a frictionless pulley of mass 2 kg as shown in the figure. The mass is released from a height of 1.6m from the ground. With what velocity does it strike the ground?

Water flows through a horizontal pipe of varying cross-section at a rate of 0.314 m³/s. The velocity of water at a point where the radius of the pipe is 10 cm is

A thick metal wire of density \( \rho \) and length \( L \) is hung from a rigid support. The increase in length of the wire due to its own weight

The value of acceleration due to gravity at a height equal to half the radius of the Earth, from its surface

Among the given pair of vectors, the resultant of two vectors can never be 3 units. The vectors are