List of top Physics Questions

Among the following, the equation representing a progressive wave is:
In a space having electric field \( \vec{E} = A(x\hat{i} + y\hat{j}) \), the potential at point (10 m, 20 m) is zero. Then the potential at the origin is: (Given \( A = 10 \, \text{Vm}^{-2} \))
A charge \( Q \) is to be divided between two objects. The values of the charges on the objects so that the electrostatic force between them will be maximum is:
A beam of light reflects and refracts at the surface between air and glass. The index of refraction of the glass is \(1.4\). If the refracted and reflected rays are perpendicular to each other, then the angle of incidence in the air is:
A ray of light is incident at \(30^\circ\) from a medium of refractive index 2 into a medium of refractive index 1. Then the angle of refraction is:
Electric potential due to a space is given by: \[ \phi(x, y, z) = \phi_0 \cdot \frac{x_0}{x} \] where \( x_0 = 5\,\text{m}, \phi_0 = 8\,\text{V} \). Find the electric field at the point (10 m, 5 m, 5 m).
The rms speed of oxygen at room temperature is about \(500 \, \text{m/s}\). The rms speed of hydrogen at the same temperature is about
A Carnot engine operating between temperatures \( T_H = 600\,K \) and \( T_C = 300\,K \), absorbs \( Q_H = 800 \, \text{J} \) of heat from the source. The mechanical work done per cycle is:
A body cools down from \(75^\circ C\) to \(65^\circ C\) in 10 minutes. It will cool down from \(65^\circ C\) to \(55^\circ C\) in a time
A copper wire of length 2.4 m and an aluminum wire of length 0.7 m, both having diameter 2 mm, are connected end to end. When stretched by a load, the obtained elongation is found to be 0.6 mm. The applied load is
(Given: Young’s modulus of copper \( Y_C = 1.2 \times 10^{11} \, \text{Nm}^{-2} \), Young’s modulus of aluminum \( Y_A = 0.7 \times 10^{11} \, \text{Nm}^{-2} \))
The angular momentum of a wheel having a rotational inertia of \( 0.2 \, \text{kg} \, \text{m}^2 \) about its symmetric axis decreases from \( 4 \) to \( 2 \, \text{kg} \, \text{m}^2 \, \text{s}^{-1} \) in \( 4 \, \text{s} \). The average power of the wheel is
A force $\vec{F} = 4\hat{i} - 15\hat{j}$ N acts on a body resulting in a displacement of $6\hat{i}$. If the body had kinetic energy of 7 joules at the beginning of the displacement, the kinetic energy at the end of the displacement is
A pendulum is oscillating at a frequency of \( 8 \, \text{Hz} \). Suddenly the string of the pendulum is clamped at its midpoint. Then the new frequency of oscillations is
Time period of a simple pendulum is \( 4 \, \text{s} \) at a place on the earth where the acceleration due to gravity is \( \pi^2 \, \text{m/s}^2 \). Then the length of the pendulum in meters is
Consider a force $F = K x^3$ which acts on a particle at rest. The work done by the force for the displacement of 2 m is ($K = 2 \, \text{N m}^{-3}$)
An object of mass 3 kg is tied by a string of negligible mass to a ceiling and held such that the string is taut. The object is released suddenly such that the string remains taut. It’s acceleration when released is (acceleration due to gravity = 10 m s$^{-2}$)
An object of mass 3 kg is tied by a string of negligible mass
The centre of mass of a homogeneous semi-circular plate of radius $r$ is located at A as shown in the figure. The distance $OA$ is
centre of mass of a homogeneous semi-circular plate of radius
The dot product of unit vectors $\hat{n}_1$ and $\hat{n}_2$ that are parallel to $5\hat{i} + 12\hat{j}$ and $3\hat{i} + 4\hat{j}$ respectively is
A sphere rolls down from the top of an inclined plane which makes an angle $30^\circ$ with the edge of a horizontal roof of a house. If the highest and lowest points of the inclined plane are 8.75 m and 3.75 m respectively from the ground then the horizontal distance from the lower edge of the roof at which the sphere hits the ground is (acceleration due to gravity = 10 m s$^{-2}$)
At the moment $t = 0$, a time dependent force $F = at$ (where $a$ is constant equal to 1 N s$^{-1}$) is applied on a body of mass 1 kg resting on a smooth horizontal plane as shown in the figure. If the direction of this force makes an angle $45^\circ$ with the horizontal, then the velocity of the body at the moment it leaves the plane is (acceleration due to gravity = 10 m s$^{-2}$)
mass 1 kg resting on a smooth horizontal plane
If the dimensional formula of (Energy $\times$ speed) is $[M^a L^b T^c]$ then $a, b$ and $c$ are
When two mutually perpendicular alternating magnetic field superimposed on each other, the resulting field is:

Match List-I with List-II.
Choose the correct answer from the options given below:

 List I(components of reactor) List-II(Function)
AUraniumIThe reaction rate can be controlled by it.
BModeratorIISlows down the fast-moving neutrons
CControl rodIIIUsed for fission reaction
DCoolantIVTransfers heat from core to turbine

 

A small circular loop of area $A$ and resistance $R$ is fixed on a horizontal $x y$-plane with the center of the loop always on the axis $\hat{n}$ of a long solenoid The solenoid has $m$ turns per unit length and carries current $I$ counterclockwise as shown in the figure The magnetic field due to the solenoid is in $\hat{ n }$ direction List-I gives time dependences of $\hat{ n }$ in terms of a constant angular frequency $\omega$ List-II gives the torques experienced by the circular loop at time $t=\frac{\pi}{6 \omega}$, Let $\alpha=\frac{A^2 \mu_0^2 m^2 I^2 \omega}{2 R}$ 
A small circular loop of area

Column I

Column II

I

$\frac{1}{\sqrt{2}}(\sin \omega t \hat{j}+\cos \omega t \hat{k})$

P

0

II

$\frac{1}{\sqrt{2}}(\sin \omega t \hat{i}+\cos \omega t \hat{j})$

Q

$-\frac{\alpha}{4} \hat{i}$

III

$\frac{1}{\sqrt{2}}(\sin \omega t \hat{i}+\cos \omega t \hat{k})$

R

$\frac{3 \alpha}{4} \hat{i}$

IV

$\frac{1}{\sqrt{2}}(\cos \omega t \hat{i}+\sin \omega t \hat{k})$

S

$\frac{\alpha}{4} \hat{j}$

 

 

T

$-\frac{3 \alpha}{4} \hat{i}$
















Which one of the following options is correct?

List I describes thermodynamic processes in four different systems List II gives the magnitudes (either exactly or as a close approximation) of possible changes in the internal energy of the system due to the process
 

List I

List II

I

$10^{-3} kg$ of water at $100^{\circ} C$ is converted to steam at the same temperature, at a pressure of $10^5 Pa$ .The volume of the system changes from $10^{-6} m ^3$ to $10^{-3} m ^3$ in the process .Latent heat of water $=2250 kJ / kg$

P

2KJ

II

$0.2$ moles of a rigid diatomic ideal gas with volume $V$ at temperature $500 K$ undergoes an isobaric expansion to volume $3 V$ Assume $R=80 Jmol ^{-1} K ^{-1}$

Q

7KJ

III

On mole of a monatomic ideal gas is compressed adiabatically from volume $V=\frac{1}{3} m ^3$ and pressure $2 kPa$ to volume $\frac{v}{8}$

R

4KJ

IV

Three moles of a diatomic ideal gas whose molecules can vibrate, is given $9 kJ$ of heat and undergoes isobaric expansion

S

5KJ

 

 

T

3KJ

Which one of the following options is correct?