List of top Physics Questions

A particle is moving in an elliptical orbit as shown in the figure. If $p$, $L$, and $r$ denote the linear momentum, angular momentum, and position vector of the particle (from focus $O$) respectively at a point $A$, then the direction of $\alpha = p \times L$ is along

A solid cylinder of radius $ R $ is at rest at a height $ h $ on an inclined plane. If it rolls down, then its velocity on reaching the ground is:

A system of two blocks of masses m = 2 kg and M = 8 kg is placed on a smooth table as shown in the figure. The coefficient of static friction between two blocks is 0.5. The maximum horizontal force F that can be applied to the block of mass M so that the blocks move together will be

A block of mass 2 kg moving on a horizontal surface with speed of 4 ms^–1 enters a rough surface ranging from x = 0.5 m to x = 1.5 m. The retarding force in this range of rough surface is related to distance by F = –kx where k = 12 Nm^–1. The speed of the block as it just crosses the rough surface will be

One end of a massless spring of spring constant k and natural length \(l_0\) is fixed while the other end is connected to a small object of mass \(m\) lying on a frictionless table. The spring remains horizontal on the table. If the object is made to rotate at an angular velocity \(ω\) about an axis passing through fixed end, then the elongation of the spring will be :

Two masses \(M_1\) and \(M_2\) are tied together at the two ends of a light inextensible string that passes over a frictionless pulley. When the mass \(M_2\) is twice that of \(M_1\), the acceleration of the system is \(a_1\). When the mass \(M_2\) is thrice that of \(M_1\), the acceleration of the system is \(a_2\). The ratio \(\frac{a_1}{a_2}\) will be

A particle is performing simple harmonic motion. Equation of its motion is \( x = 5 \sin \left( 4t - \frac{\pi}{6} \right) \), \( x \) being the displacement from the mean position. Velocity (in ms\(^{-1}\)) of the particle at the instant when its displacement is 3, will be

Two uniformly charged spherical conductors, A and B of radii 5 mm and 10 mm are separated by a distance of 2 cm. If the spheres are connected by a conducting wire, then in equilibrium condition, the ratio of the magnitude of the electric fields at surface of the spheres A and B will be

A conducting sphere is charged. If the electric field at a distance of 20 cm from the center of this sphere is 1.2x103NC-1 and points radially inward, the net charge on this sphere is

The expression for torque ‘τ’ experienced by an electric dipole of dipole moment ‘P’ in an external uniform electric field ‘E’ is given by :

Given below are two statements:
Statement I: A time varying electric field is a source of changing magnetic field and vice-versa. Thus a disturbance in electric or magnetic field creates EM waves.
Statement II: In a material medium, the EM wave travels with speed
\(V=\frac{1}{\sqrt{µ0ε0}}\) In the light of the above statements, choose the correct answer from the options given below.

A velocity selector consists of electric field \(\overrightarrow E=E\hat K\) and magnetic field \(\overrightarrow B=B\hat j\) with \(B = 12 \;mT\). The value of E required for an electron of energy \(728\) \(eV\) moving along the positive x-axis to pass undeflected is (Given, mass of electron = \(9.1 × 10^{–31}\) kg)

A spherically symmetric charge distribution is considered with charge density varying as
\(ρ(r) =   \begin{cases}     ρ_0(\frac 34−\frac rR)      &; \text{for} \ r≤R\\     Zero  &; \text{for}\ r>R    \end{cases}\)
Where, r(r<R) is the distance from the centre O (as shown in figure) The electric field at point P will be :

Which of the following diagram represents the variation of the electric field with distance \( r \) from the centre of a uniformly charged non-conducting sphere of radius \( R \)?

The electric potential for an electric field directed parallel to the X-axis is shown in the figure. Choose the correct plot of electric field strength.

Consider a uniform sphere of radius R and mass M. A spherical cavity of radius R/2 is made in the sphere as shown in figure. The magnitude of the gravitational intensity at a point O on the surface of the cavity is

Two media A and B are separated by a plane boundary surface. The speed of light in medium A and B are 2 x 10⁸ m/s and 2.5 x 10⁸ m/s respectively. The critical angle for which a ray of light going from A to B will have total internal reflection is A

Energy needed in breaking a liquid drop of radius \( R \), into \( n \) smaller drops each of radius \( r \), is
[ \( T \) - Surface tension of the liquid ]

An object of mass \(10 \, \text{kg}\) is released from rest in a liquid. If the object moves a distance of \(2 \, \text{m}\) while sinking in a time duration of \(1 \, \text{s}\), then the mass of the liquid displaced by the submerged object is (Given: Acceleration due to gravity \( g = 10 \, \text{m/s}^2 \))

Consider the following statements:
(A) Whentemperature increases, the viscosity of gases increases and viscosity of liquids decreases.
(B) Water does not wet an oily glass because the cohesive force of oil is less than that of water.
(C) A liquid will wet a surface if the angle of contact is greater than 90◦.
Which of the following is true?