List of top Physics Questions

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 \( \tau \).
Two parallel wires carry currents of 5 A and 4 A in opposite directions. The wires are separated by a distance of 4 cm. Find the net magnetic field at a point midway between the two wires.
A metal has a work function \( \phi \). When light of wavelength \( \lambda \) is incident on it, the kinetic energy of the ejected electrons is 2 eV. Find the new kinetic energy of the ejected electrons when light of wavelength \( \lambda/2 \) is used.
A mass of 100 g is projected with an initial velocity of 12 m/s at an angle of 60° with the horizontal. Find the difference between the kinetic energy at the point of projection and the kinetic energy at the highest point.
A force \( \mathbf{F} = 2\hat{i} + 3\hat{j} + 5\hat{k} \) acts on a particle moving in the direction of \( \mathbf{r} = 2\hat{i} + 3\hat{j} + \beta \hat{k} \). Find the value of \( \beta \) when the work done is zero.
In a sound wave, the displacement of the air particles follows the equation \( y = A \cos(kx - \omega t) \). What is the wave velocity?
What is the time period of a simple pendulum of length \( L \) and acceleration due to gravity \( g \)?
In a resistive circuit, the power dissipated by a resistor \( R \) when a current \( I \) flows through it is given by \( P = I^2 R \). What happens to the power when the current is doubled?
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 \( \phi = 2 \, \text{eV} \)?
Monochromatic light of green color is used in Young’s double slit experiment and an interference pattern is observed on a screen. If the green light is replaced by red monochromatic light of the same intensity, how will the fringe width of the interference pattern be affected? Justify your answer.
Write the conditions under which two light waves originating from two coherent sources can interfere each other (i) constructively, and (ii) destructively, in terms of wavelength. Can these be applied for two lights originating from two sodium lamps? Give reason.
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
A square loop MNPK of side \( l \) carrying a current \( I_2 \) is kept close to a long straight wire in the same plane and the wire carries a steady current \( I_1 \) as shown in the figure. Obtain the magnitude of magnetic force exerted by the wire on the loop.
square loop MNPK of side l carrying a current I2
In which cases does a charged particle not experience a force in a magnetic field?
In Bohr’s model of hydrogen atom, find the percentage change in the radius of its orbit when an electron makes a transition from \( n = 3 \) state to \( n = 2 \) state.
In Young's double slit experiment, the screen is moved 30 cm towards the slits. As a consequence, the fringe width of the pattern changes by 0.09 mm. If the slits separation used is 2 mm, calculate the wavelength of light used in the experiment.
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: