List of top Physics Questions

Find the wavelength in (nm) of incident radiation where the work function is 4.12 eV and the stopping potential is 4V. Given that \( h \nu = 1242 \, \text{eV} \cdot \text{nm} \).
Two charges +7 mC and -4 mC at coordinates (-7, 0, 0) and (7, 0, 0), respectively, find the electrostatic potential energy. \[ \epsilon_0 = 8.85 \times 10^{-12} \, \text{C}^2 \, \text{N}^{-1} \, \text{m}^{-2}. \]
The value of \( E_0 \) is 9.3 V/m and \( c \) is \( 3 \times 10^8 \, \text{m/s} \). Find the value of \( B_0 \).
Find the charge on the capacitor in the steady state. \vspace{1cm} \includegraphics[width=0.7\textwidth]{a.png}
If the angle of prism equals the angle of minimum deviation, and given that the refractive index \( \mu = \sqrt{3} \), then the angle of the prism is:
A proton is moving with a uniform velocity of \( 2 \times 10^8 \, \text{m/s} \) in uniform magnetic and electric fields which are perpendicular to each other. If the electric field is switched off, then the proton moves in a circular path of radius \( 1.6 \times 10^{-5} \, \text{m} \). Then the magnetic field \( B \) is:
Statement 1: Hotter water moves faster than cold water.
Statement 2: Soap water has a higher surface tension than fresh water.
If angles of projection for two projectiles are 30° and 60° then the ratio of velocities at maximum height is:
In a bag, there are 6 white balls and 4 black balls. Two balls are drawn at random. What is the probability that both balls are white?
A solid sphere of mass \( M \), radius \( R \) exerts a gravitational force \( F \) on a point mass. Now a concentric spherical mass \( \frac{M}{7} \) is removed. What is the new force?
Find the current in the circuit at steady state, given \( R = 2 \, \Omega \).
An equiconvex lens of focal length \( f \) is cut into four parts as shown in the diagram. The focal length of each part is
A force \( \mathbf{F} = \hat{i} + 2\hat{j} + 2\hat{k} \) acts on a particle at position vector \( \mathbf{r} = 2\hat{i} + 3\hat{j} + 4\hat{k} \). Find the torque \( \tau \).
What is the time period of a simple pendulum of length \( L \) and acceleration due to gravity \( g \)?
A block of mass \( m \) is moving with velocity \( v \) on a smooth horizontal surface. If a constant force \( F \) is applied to the block, what is the work done by this force after 5 seconds?
In the context of the photoelectric effect, what is the threshold frequency \( f_0 \) for a metal if the work function is \( \phi = 2 \, \text{eV} \)?
The cut-off voltage \( V_0 \) versus frequency \( \nu \) of the incident light curve is a straight line with a slope of \( \frac{h}{e} \). Explain this observation.
The figure shows the plot of magnitude of induced emf (\( \varepsilon \)) versus the rate of change of current in two coils ‘1’ and ‘2’. Which coil has a greater value of self-inductance and why?
plot of magnitude of induced emf
In an electromagnetic wave travelling in free space, the amplitude of magnetic field is \( 6.0 \times 10^{-4} \ \text{T} \). The amplitude of its electric field is:
The magnetic flux linked with a closed coil (in Wb) varies with time \( t \) (in s) as \( \phi = 5t^2 + 4t - 2 \). If the resistance of the circuit is 14 \( \Omega \), the magnitude of induced current in the coil at \( t = 1 \) s will be:
Which of the following substances has magnetic permeability less than that of free space?
Three wires A, B, and C of the same material have lengths and area of cross-sections as \( (2l, \frac{A}{2}) \), \( (l, A) \) and \( (\frac{l}{2}, 2A) \), respectively. If the resistances of these wires are \( R_A, R_B, R_C \) respectively, then:
A bar magnet is held with its length along the axis of a closed coil. Initially, the south pole of the magnet faces the coil. If the magnet is moved towards the coil, explain how a current is induced in the coil and in what direction.
When current in a coil changes at a steady rate from 8 A to 6 A in 4 ms, an emf of 1.5 V is induced in it. The value of self-inductance of the coil is :
The materials having negative magnetic susceptibility are :