MAH-MHT CET (PCM/PCB) entrance exam Question Bank Solutions for Physics

An electron is accelerated through a potential difference of 10,000 V. Its de Broglie wavelength is, ______.

(nearly) (m_e= 9 x 10^-31 kg)

The electron in the hydrogen atom is moving with a speed of 1.5 x 10⁶ m/s in an orbit of radius 2 Å. Magnetic moment of the revolving electron is ____________.

A particle is executing simple harmonic motion with frequency f. The frequency at which its kinetic energy changes into potential energy is ______.

Instrument which measures alternating current is based on ____________.

A 60 `Omega` electric heater is connected to a 200 V, 50 Hz mains supply. The peak value of electric current flowing in the circuit is approximately ______.

Eddy currents are produced in a material when it is ____________.

The equation of a wave is y = 60 cos (1800t - 6x), where y is in microns, t in seconds, and x in metres. The ratio of maximum particle velocity to the wave velocity of wave propagation is ______.

Which one of the following properties is not possessed by a photon?

A coil having effective area A, is held with its plane normal to a magnetic field of induction B. The magnetic induction is quickly reduced to 25% of its initial value in 4 s. Then e.m.f. induced across the coil will be ____________.

A conducting circular loop is placed in a uniform magnetic field 0.02 T with its plane perpendicular to the magnetic field. The radius of the loop starts shrinking at 2 mm/s. The induced e.m.f. in the loop when the radius is 2 cm will be ____________.

What is the r.m.s. value of an alternating current which when passed through a resistor produces heat which is four times of that produced by a direct current of 3 ampere in the same resistor?

In a hydrogen atom, an electron of charge e revolves in a orbit of radius r with speed v. Then, the magnetic moment associated with electron is ______.

Equation of a plane progressive wave is given by `"y" = 0.6  "sin"2pi ("t" - "x"/2)`. On reflection from 48. denser medium its amplitude become `2/3` of the amplitude of the incident wave. The equation of the reflected wave is ____________.

The rate of change of magnetic flux density through a circular coil of area 10^-2 m² and number of turns 200 is 10³ Wb/m² s. The value of induced e.m.f. will be ____________.

The equation of a wave of amplitude 0.02 m and period 0.04 s travelling along a stretched string with a velocity of 25 m/s will be ____________.

Which one of the following proportionality represents the relation between orbital magnetic moment M₀ and orbital angular momentum L₀ of an electron?

Metal rings 'P' and 'Q' are lying in the same plane where current 'I' is increasing steadily. The induced current in metal rings is shown correctly in figure.

The r.m.s. value of induced voltage in a coil of 25 turns each of area 30 sq. cm. rotating at 2000 r.p.m. about an axis at right angles to magnetic field is (B = 5 x 10^-4 Wb/m²) ____________.

A magnetic field of 2 x 10^-2 T acts at right angles to a coil of area 50 cm² with 100 turns. The average e.m.f. induced in the coil is 0.2 V, when it is removed from the field in time t. The value of t is ____________.

The electric potential V at any point O (x, y, z all in metres) in space is given by V = 4x² volt. The electric field at the point (1 m, 0, 2m) in volt/metre is ____________.