List of top Physics Questions

The magnetic field of a cylindrical magnet that has a pole-face radius $2.8 \,cm$ can be varied sinusoidally between minimum value $16.8 \,T$ and maximum value $17.2 \,T$ at a frequency of $\frac{60}{\pi}\,Hz$ Cross section of the magnetic field created by the magnet is shown. At a radial distance of $2\, cm$ from the axis, find the amplitude of the electric field (in $mN \,C^{-1})$ induced by the magnetic field variation.
The lower end of a capillary tube of radius r is placed vertically in water then with the rise of water in the capillary heat evolved is
The linear strain in x ,y and z directions are $e_x,e_y$ and $e_z$. respectively. Then the volumetric strain is given by
The linear momentum of a $3\, MeV$ photon is
The level of water in a tank is 5m high. A hole of area $1\,cm^2$ is made at the bottom of the tank. The rate of leakage of water from the hole in $m^3/s$ is $(g=10\,ms^{-2})$
The length of the simple pendulum which ticks seconds is
The length of a solenoid is 0.1m and its diameter is very small. A wire is wound over in two layers. The number of turns in the inner layer is 50 and that on the outer layer is 40. The strength of current flowing in two layers in the same direction is 3 ampere. The magnetic induction in the middle of the solenoid will be
The length of a wire required to manufacture a solenoid of length l and self-induction L is (cross-sectional area is negligible)
The length of a seconds pendulum is
The length of a microscope is 14 cm and for relaxed eye the magnifying power is 25. The focal length of the eye piece is 5 cm. What is the distance of the object from the objective ?
The length of a magnet is large compared to its width and breadth. The time period of its oscillation in a vibration magnetometer is 2 s. The magnet is cut along its length into three equal parts and three parts are then placed on each other with their like poles together. The time period of this combination will be
The length of a conductor is halved. Its conductivity will be
The least random state of $H_2O$ system is
The least value for the common base transistor amplifier is in the case of
The knee voltage of a p-n junction diode is 0.8 V and the with of the depletion layer is 2 $\mu m$, the electric field in the depletion layer is
The kinetic energy of a particle executing SHM is maximum, when its displacement is equal to
The interference differs from diffraction in that:
The interference finges formed by a thin oil film on water, when seen in the yellow light of sodium lamp will be :
The interference phenomenon can take place
The intensity of a wave is defined as the energy transmitted per unit area per second. Which of the following represents the dimensional formula for the intensity of the wave?
The inner and outer radius of a toroid core are $28 \,cm$ and $29\, cm$ respectively and around the core $3700$ turns of a wire are wounded. If the current in the wire is $10\, A$, then the magnetic field inside the core of the toroid is
The inductance L of a solenoid of length l , whose windings are. made of material of density D and resistivity $\rho$ is (the winding resistance is R)
The induced emf in a coil is independent of
The induced emf in a coil rotating in a magnetic field is maximum when the angle between the plane of the coil and the direction of field is :
The incorrect statement for saturation current in a photoelectric cell is