List of top Physics Questions

The balancing length of a potentiometer is at 120 cm. On shunting the cell with a resistance of 4 ohm, the balancing point shifts to a length of 60 cm. The internal resistance of the cell is:
A wire of weight W and area of cross-section A elongates under its own weight. If Y is the Young's modulus and \(\sigma\) is the Poisson's ratio of the material of the wire, then the fractional change in the radius of the wire is:
In the following circuit, the value of Y is:
The maximum kinetic energy of a pendulum executing simple harmonic motion is E. If the length of the pendulum is doubled and the amplitude of motion is halved, then the maximum kinetic energy of the pendulum is:
Interference fringes produced by a double slit arrangement using a monochromatic light of wave length 5,890Å have an angular fringe width \( 0.28^\circ \). If the entire arrangement is immersed in water, the new angular fringe width will be (\( ^a\mu_w = 4/3 \)):
The three graphs represent acceleration Vs time for objects that have positive velocity at time \( t_1 \). Which graphs show the objects that move with increasing velocity for the entire time interval between \( t_1 \) and \( t_2 \)?
The pressure and density of a diatomic gas (\( \gamma = 7/5 \)) change adiabatically from \( (p, d) \) to \( (p', d') \). If \( \frac{d'}{d} = 32 \), then \( \frac{p'}{p} \) should be:
A metal sheet is placed in a magnetic field whose magnitude changes from zero to maximum. The direction of eddy currents produced in the plate is shown in the figure. Then the direction of magnetic field is:
A capacitor of 10 \(\mu\text{F}\) charged up to 200 V is connected in parallel with another capacitor of 20 \(\mu\text{F}\) charged up to 50 V. The common potential is:
A particle having charge 'q' enters a uniform transverse magnetic field \( \vec{B} \). It is deflected through a distance 'x' while travelling a distance 'y' as shown in figure. The magnitude of the momentum of the particle is:
A particle executes two simple harmonic motions along mutually perpendicular axes, given by \( x = A \sin(\omega_1 t) \) and \( y = B \cos(\omega_2 t) \) where \( A \neq B \) and \( \omega_1 = \omega_2 \). Which of the following best describes the resultant motion of the particle?
A current carrying circular coil of radius 'r' produces a magnetic induction of 1 T at its centre. The magnetic induction at a distance of \(\sqrt{3}r\) on its axis from its centre is:
If the temperature of a steel solid sphere of mass 4 kg and radius 5 cm is increased by 10°C then the increase in the moment of inertia of the sphere about its diameter is: (Coefficient of linear expansion of steel = \( 1.2 \times 10^{-5} \text{K}^{-1} \))
In the circuit shown, the current through 8 ohm is same before and after connecting E. The value of E is:
Convex lens of focal length 20 cm and a concave lens of focal length of 30 cm are separated by a distance of 10 cm. Equivalent power of this arrangement is:
If $f_{m}$ is a modulating frequency and $f_{c}$ is carrier wave frequency, then Bandwidth in Amplitude Modulated wave is
A body of mass $5\text{ kg}$ is projected vertically upwards from a point $X$ from the ground with an initial speed of $20\text{ ms}^{-1}$. It rises to a point $Y$ where its kinetic energy is reduced to $400\text{ J}$. If the body experiences a constant air resistance of $10\text{ N}$ throughout its motion, then the vertical distance between $X$ and $Y$ is (Acceleration due to gravity $=10\text{ ms}^{-2}$)
Two identical balls each of mass $\frac{40}{3}$ g carry equal and opposite charge. They are suspended from a horizontal plate by silk threads each of length 1 m with a separation of 1.5 m between points of suspension. At equilibrium, if the distance between the balls is 30 cm then magnitude of charge on each ball is (Acceleration due to gravity $= 10 \text{ ms}^{-2}$)
A blackened platinum wire of surface area $10^{-5}\text{m}^{2}$ is maintained at temperature of 3000K. At what rate the wire is loosing energy [Stefan-Boltzmann constant $\sigma=5.67\times10^{-8}\text{W m}^{-2}\text{K}^{-4}$]
Cars $X$ and $Y$ begin the race simultaneously with velocities $8\text{ ms}^{-1}$ and $4\text{ ms}^{-1}$, moving in a straight line with uniform accelerations $2\text{ ms}^{-2}$ and $4\text{ ms}^{-2}$ respectively. If they reach final point at the same instant, then the length of the path is
A particle starting from the origin executes simple harmonic motion along x-axis. Its velocity at any instant t is given by $v_{x}=22 \cos(\frac{\pi t}{2}) \text{ cm s}^{-1}$. The total distance covered by the particle in time $t=4.5 \text{ sec}$ is
The refractive index of water is $\frac{4}{3}$ and that of glass is $\frac{3}{2}$. The refractive index of glass with respect to water is
The atomic number (Z) of a hydrogen like atom whose shortest wavelength of Brackett Series is same as the shortest wavelength of Balmer series of hydrogen atom is
The rms speed of oxygen molecule at some temperature is $150 \text{ ms}^{-1}$. Then the rms speed of hydrogen molecule at the same temperature is
Binding energy per nucleon of deuteron and Helium nuclei are 1.1 MeV and 7 MeV respectively. If a single Helium nucleus was formed by adding two Deuterons, the energy released is