List of top Physics Questions

In a moving coil galvanometer, the coil having $ 500 $ turns and an average area of $ 4 \,cm^{2} $ carries a current of $ 0.1 \,A $ and is set parallel to a magnetic field with a torque of $ 0.15\, N \,m $ . The strength of the magnetic field is
An organ pipe open at both ends has fundamental frequency $ f $ in air. If the pipe is dipped vertically in water such that $ 1/4^{th} $ of its length is inside water, then the fundamental frequency of the air column in it is
The pair of rigid bodies with mass M and radius R, having the moment of inertia $\frac{MR^{2}}{2}$ can be
The operating point of transistor amplifier should be in
The electric flux passing through $a$ cube of side $ a $ , which holds a charge $ q $ at one of its corners is
For a thin lens with radii of curvatures and $ R_{1} $ and $ R_{2} $ , refractive index $ n $ and focal length $ f $ , the factor $ \left(\frac{1}{R_{1}}-\frac{1}{R_{2}}\right) $ is equal to
The angle between the linear momentum and angular momentum of a particle moving along a circle is
The distance of closest approach for an alpha nucleus of velocity $ v $ bombarding a stationary heavy nucleus target of charge $ Ze $ is directly proportional to
Identify the correct statement about a stationary wave
A solid cylinder of radius $R$ made of a material of thermal conductivity $K_1$ is surrounded by a cylindrical shell of inner radius $R$ and outer radius $2R$ made of a material of thermal conductivity $K_2$. The two ends of the combined system are maintained at two different temperatures. Then there is no loss of heat across the cylindrical surface and the system is in steady state. The effective thermal conductivity of the system is
The processes $ 3, 2 $ and $ 1 $ represent the respective isobaric, isothermal and adiabatic expansion of one mole of a gas initially at a pressure $ P $ from volume $ V $ to $ 2V $ . The work done is
For an ideal step-down transformer, the quantity which is constant for both the coils is
If the ratio of the mechanical energy of a mass whose oscillations are damped to that of its free oscillations is $ e^{-3 t/m} $ , then the ratio of the amplitudes of the damped oscillations to that of free oscillations is
If the coefficient of linear expansion of a metal is $ 0.00002 \,K^{-1} $ , then the necessary increase in temperature of the metal rod in order to increase its length by $ 2\% $ is
The temperature of source of a Carnot engine of efficiency $ 20\% $ when the heat exhausted is at $ 240 \,K $ is
For an object placed in front of a convex mirror of focal length $ f $ , its image is formed
Two charges of equal amount +Q are placed on a line. Another charge q is placed at the mid-point of the line. The system will be in equilibrium if the value of q is
The increase in electrostatic potential energy of a dipole of moment p when it is taken from parallel to anti-parallel orientation in an electric field E is
A micro-ammeter gives full scale deflection at 100 $\mu$A. Its resistance is 2k$\Omega$. The resistance required to convert it to a voltmeter reading 1V is
A particle of mass ????and carrying a charge ????enters with a velocity ????perpendicular to a uniform magnetic field. The time period of rotation of the particle
If$I_{1}$and$I_{2}$ be the sizes of real images for two positions of a convex lens between object and screen,then the size of the object is
If a bar magnet of magnetic moment M is kept in a uniform magnetic field B, its time period of oscillation is T. In the same magnetic field, the time period of another magnet of same dimension and same mass but of moment M/4 is,
If the nuclear radius of $^{27}Al$ is 3.6 Fermi, the approximate nuclear radius of $^{64}Cu$ in Fermi is
An n-p-n transistor of current gain 80 in common emitter mode gives emitter current equal to 8.1 mA. The base current is
A zener diode has break down voltage of 5.0 V. The resistance required to allow a current of 100 mA through the zener in reverse bias when connected to a battery of emf 12 V is