List of top Physics Questions

Two nuclei have mass numbers A and B respectively. The density ratio of the nuclei is______.
Fill in the blank with the correct answer from the options given below.

In a p-type semiconductor, the acceptor level is situated 50 meV above the valence band. The maximum wavelength of light required to produce a hole will be:

According to Bohr’s Model:
(A) The radius of the orbiting electron is directly proportional to ‘n’.
(B) The speed of the orbiting electron is directly proportional to 1/n. (C) The magnitude of the total energy of the orbiting electron isdirectly proportional to 1/n².
(D) The radius of the orbiting electron is directly proportional to n².

The study of radioactive decay results in the emission of particles, leading to four observations: (A) No change in atomic and mass number, (B) Atomic number decreases by 1, (C) Study of radioactive decay of unstable nuclei resulting in emission of a
particle leads us to four different observations listed below:
(A) Nochange in atomic number and mass number.
(B) Nochange in mass number but the atomic number decreases by 1.
(C) Nochange in mass number but the atomic number increases by 1.
(D) Atomic number decreases by 2 and the mass number decreases by 4.
Arrange the particles emitted in the above four cases in correct sequence:

For a full wave rectifier, if the input frequency is 50 Hz, the output frequency will be_____
Fill in the blank with the correct answer from the options given below.

Given below are V versus I graphs for different types of p-n junction diodes marked A, B, C, and D.

The correct sequence of graphs corresponding to forward biased p-n junction; Zener
diode; Photo diode and Solar cell in order is _________.
Fill in the blank with the correct answer from the options given below.

Which of the following particles will experience the maximum magnetic force (magnitude) when projected with the same velocity perpendicular to the magnetic field?

In the experiment to determine the galvanometer resistance by half-deflection method, the plot of \(\frac{1}{ \theta}\) vs the resistance (R) of the resistance box is shown in the figure. The figure of merit of the galvanometer is .............. ×10^–1 A/division. [The source has emf 2V]

Resistance of a wire at \(0^\circ C\), \(100^\circ C\) and \(t^\circ C\) is found to be \(10 \, \Omega\), \(10.2 \, \Omega\) and \(10.95 \, \Omega\) respectively. The temperature \(t\) in Kelvin scale is ______.

A stationary particle breaks into two parts of masses \(m_A\) and \(m_B\), which move with velocities \(v_A\) and \(v_B\), respectively. The ratio of their kinetic energies (\(K_B : K_A\)) is:

Two different adiabatic paths for the same gas intersect two isothermal curves as shown in the \(P-V\) diagram. The relation between the ratio \(\frac{V_a}{V_d}\) and the ratio \(\frac{V_b}{V_c}\) is:

A series LCR circuit is subjected to an AC signal of 200 V, 50 Hz. If the voltage across the inductor (L = 10 mH) is 31.4 V, then the current in this circuit is ________ :

Two rings of equal radius \(R\) arranged perpendicular to each other with common center at \(C\), carrying equal current \(I\). Find magnetic field at \(C\).

In an ammeter, 5% of the main current passes through the galvanometer. If resistance of the galvanometer is G, the resistance of ammeter will be :

The magnetic field in a plane electromagnetic wave is \[ B_y = (3.5 \times 10^{-7}) \sin \left( 1.5 \times 10^3 x + 0.5 \times 10^{11} t \right) \, \text{T}. \] The corresponding electric field will be:

A coil of negligible resistance is connected in series with \(90 \, \Omega\) resistor across \(120 \, \text{V}, \, 60 \, \text{Hz}\) supply. A voltmeter reads \(36 \, \text{V}\) across resistance. Inductance of the coil is:

A body of mass \(2 \, \text{kg}\) begins to move under the action of a time-dependent force given by \(\vec{F} = (6t \, \hat{i} + 6t^2 \, \hat{j}) \, \text{N}\). The power developed by the force at the time \(t\) is given by:

The magnetic moment of a bar magnet is \( 0.5 \, \text{Am}^2 \). It is suspended in a uniform magnetic field of \( 8 \times 10^{-2} \, \text{T} \). The work done in rotating it from its most stable to most unstable position is:

A heavy box of mass 50 kg is moving on a horizontal surface. If co-efficient of kinetic friction between the box and horizontal surface is 0.3 then force of kinetic friction is :

In hydrogen like system the ratio of coulombian force and gravitational force between an electron and a proton is in the order of:

Electromagnetic waves travel in a medium with a speed of \( 1.5 \times 10^8 \, \text{ms}^{-1} \). The relative permeability of the medium is \( 2.0 \). The relative permittivity will be:

The bob of a pendulum was released from a horizontal position. The length of the pendulum is 10 m. If it dissipates 10% of its initial energy against air resistance, the speed with which the bob arrives at the lowest point is: [Use, \( g : 10 \, \text{m/s}^2 \)]

There are two cubical Gaussian surface carrying charges as shown. Find ratio of fluxes through surface \(C_1\) and \(C_2\):

If the rms velocity of hydrogen gas molecules is \(V_o\), find the rms velocity of oxygen molecules at same temperature :

Two charges q and 3q are placed at a distance r from each other. Find the distance from q where the electric field is zero.