List of top Physics Questions

If the magnetic field is along the positive y-axis and the electron is moving along the positive x-axis, the direction of force on the electron is

A bar magnet of length $0.1~\text{m}$ and magnetic moment of $5~\text{Am}^2$ is placed in a uniform magnetic field of intensity $0.4~\text{T}$, with its axis making an angle of $60^\circ$ with the field. The torque on the magnet is

Changing magnetic fields can set up current loops in nearby metal bodies. They dissipate electrical energy as heat. Such currents are called

A resistor of $50~\Omega$, an inductor and a capacitor are connected in series to an AC source of peak voltage $200\sqrt{2}~\text{V}$.
When the capacitor alone is removed, current lags voltage by $37^\circ$.
When the inductor alone is removed, current leads voltage by $37^\circ$.
The power dissipated in the LCR circuit is:

The efficiency of a bulb of $1000~\text{W}$ is $6%$. The peak value of the magnetic field produced by the electromagnetic radiation from the bulb at a distance of $1~\text{m}$ is: \[ \left( \frac{1}{4\pi \varepsilon_0} = 9 \times 10^9~\text{Nm}^2\text{C}^{-2} \right) \]

Two photons each of energy $2~\text{eV}$ incident simultaneously on a photosensitive material of work function $3~\text{eV}$. The maximum kinetic energy of the emitted photoelectrons is

An electron in the ground state of hydrogen atom absorbs $10.2~\text{eV}$ energy. The orbital angular momentum of the electron increases by

If the speed of light was half the present value, the energy released in a nuclear reaction decreases by

In the given logic circuit, if A and B are the inputs, then P and Q are respectively
\

An oscillator is an amplifier with

A message signal of frequency $20~\text{kHz}$ and peak voltage $20~\text{V}$ is used to modulate a carrier of peak voltage $100~\text{V}$. The modulation index is

An electric dipole is placed at an angle of 30° with an electric field of intensity 2x10⁵ NC-1. It experiences a torque equal to 4 Nm. Calculate the magnitude of charge on the dipole, if the dipole length is 2cm.

An insulated copper wire of 100 turns is wrapped around a wooden cylindrical core of the cross- sectional area 24 cm². The two ends of the wire are connected to a resistor. The total resistance in the circuit is 129. If an externally applied uniform magnetic field in the core along its axis changes from 1.5 T in one direction to 1.5 T in the opposite direction, the charge flowing through a point in the circuit during the change of magnetic field will be ________mC.

The P-V diagram of a Carnot's engine is shown in the graph below. The engine uses 1 mole of an ideal gas as working substance. From the graph, the area enclosed by the P-V diagram is
[ The heat supplied to the gas is 8000 J ]

List-I shows different radioactive decay processes and List-II provides possible emitted particles. Match each entry in List-I with an appropriate entry from List-II, and choose the correct option.

	List-I		List-II
(P)	$^{238}_{92}U → ^{234}_{91}Pa$	(1)	one 𝛼 particle and one 𝛽+ particle
(Q)	$^{214}_{82}Pb → ^{210}_{82}Pb$	(2)	three 𝛽− particles and one 𝛼 particle
(R)	$^{210}_{81}Tl → ^{206}_{82}Pb$	(3)	two 𝛽− particles and one 𝛼 particle
(S)	$^{228}_{91}Pa → ^{224}_{88}Ra$	(4)	one 𝛼 particle and one 𝛽− particle
		(5)	one 𝛼 particle and two 𝛽+ particles

In a thermodynamic pross if '$\Delta W$' and '$\Delta U$' are the work done and change in the internal energy of a system respectively, then

A slide with a frictionless curved surface, which becomes horizontal at its lower end, is fixed on the terrace of a building of height 3ℎ from the ground, as shown in the figure. A spherical ball of mass 𝑚 is released on the slide from rest at a height ℎ from the top of the terrace. The ball leaves the slide with a velocity $\hat{u}_0=u_0\hat{x}$ and falls on the ground at a distance 𝑑 from the building making an angle θ with the horizontal. It bounces off with a velocity of v and reaches a maximum height of ℎ₁. The acceleration due to gravity is 𝑔 and the coefficient of restitution of the ground is $\frac{1}{\sqrt3}$. Which of the following statement(s) is(are) correct?

A bullet from a gun is fired on a rectangular wooden block with velocity u. When the bullet travels 24 cm through the block along its length horizontally, velocity of bullet becomes $\frac{u}{3}$. Then it further penetrates into the block in the same direction before coming to rest exactly at the other end of the block. The total length of the block is:

The electric field associated with an electromagnetic wave propagating in a dielectric medium is given by $\vec{E}$=30(2𝑥̂ + 𝑦̂)sin [2𝜋 (5×10¹⁴𝑡 −$\frac{10^7}{3}z$)] Vm⁻¹. Which of the following option(s) is(are) correct? [Given: The speed of light in vacuum, 𝑐 = 3 × 10⁸ ms⁻¹]

When light of wavelength $ \lambda $ incidents on a photosensitive material, photoelectrons are emitted. If the wavelength of the incident light is reduced by 50\%, the maximum kinetic energy of the emitted photoelectrons becomes 3 times the initial maximum kinetic energy. The work function of the material is:

In the given circuit, when $ A = 1 $, $ B = 1 $ the values of $ X $ and $ Y $ respectively are

Positron is the antiparticle of

In a transistor amplifier, the voltage gain is

The electric field in $ N C^{-1} $ of an electromagnetic wave is $ E = 36 \sqrt{\pi} \sin ( \omega t - kx) $. The average energy density of the electromagnetic wave due to the electric field is:

The total energy of an electron in an orbit of hydrogen atom is $ E $. The potential energy of the electron in the same orbit is

	List-I		List-II
(P)	\(^{238}_{92}U → ^{234}_{91}Pa\)	(1)	one 𝛼 particle and one 𝛽+ particle
(Q)	\(^{214}_{82}Pb → ^{210}_{82}Pb\)	(2)	three 𝛽− particles and one 𝛼 particle
(R)	\(^{210}_{81}Tl → ^{206}_{82}Pb\)	(3)	two 𝛽− particles and one 𝛼 particle
(S)	\(^{228}_{91}Pa → ^{224}_{88}Ra\)	(4)	one 𝛼 particle and one 𝛽− particle
		(5)	one 𝛼 particle and two 𝛽+ particles