Physics MCQs for NEET — Practice Questions with Answers

The energy of the X-rays photon is 3.3$\times {10}^{-16}$J. Its frequency is :

In X-ray tube, the accelerating potential applied at the anode is V volt. The minimum wavelength of the emitted X-ray will be :

If a source is transmitting an electromagnetic wave of frequency $8.2\times {10}^6 Hz$, then the wavelength of the electromagnetic wave transmitted from the source will be :

A plane electromagnetic wave

$E_z=100 \cos (6\times {10}^{8}t+4x) V/m$

propagates in a medium of dielectric constant

If ${\mu }_0$ be the permeability and $K_0$ the dielectric constant of a medium, its refractive index is given by

If ${\epsilon }_0 and {\mu }_0$ represent the permittivity and permeability of vacuum and $\epsilon and \mu$ represent the permittivity and permeability of the medium, the refractive index of the medium is given by

The magnetic field between the plates of radius 12 cm separated by a distance of 4 mm of a parallel plate capacitor of capacitance 100 pF along the axis of plates having conduction current of 0.15 A is

A flood light is covered with a fitter that transmits red light. The electric field of the emerging beam is represented by a sinusoidal plane wave

$E_x=36 \sin (1.20\times {10}^7 z-3.6\times {10}^{15} t) V/m$

The average intensity of beam in W/$m^2$ will be

The average energy - density of electromagnetic wave given by E = (50 N/C) sin($\omega t-kx)$ will be nearly

A larger parallel plate capacitor, whose plates have an area of 1 $m^2$ are separated from each other by 1 mm, is being charged at a rate of 25.8 V/s. If the plates has dielectric constant 10, then the displacement current at this instant is