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

Light of different frequencies, whose photons have energies 3 eV and 18 eV respectively, successively illuminate a metal of work function 2 eV. The ratio of the maximum speeds of the emitted electrons will be ______.

The work function of a substance is 4.0 eV. The longest wavelength of light that can cause photo-emission from this substance is approximately (h = 6.63 × 10^-34 Js)[1eV = 1.6 × 10^-19 J]

q₁, q₂, q₃ and q₄ are point charges located at points as shown in the figure and S is a spherical gaussian surface of radius R. Which of the following is true according to the Gauss' law?

The photon of frequency vis incident on a metal surface whose threshold frequency is v₀. The kinetic energy of the emitted photoelectrons will be ____________.

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 ____________.

Following graphs show the variation of stopping potential corresponding to the frequency of incident radiation (F) for a given metal. The correct variation is shown in graph (v₀ = Threshold frequency).

Two identical circular loops of metal wire are lying on a table without touching each other. Loop-A carries a current which increases with time. ln response, the loop-B ____________.

For a particle executing simple harmonic motion, which of the following statements is NOT correct?

For a radiation of 9 GHz passing through air. The number of waves passing through 1 m length is ____________.

A planet is revolving around the sun in an elliptical orbit as shown in figure. At which point will its K.E. be maximum?

The lowest frequency of light that will cause the emission of photoelectrons from the surface of a metal (for which work function is 1.65 eV) will be ____________.

The photon of frequency vis incident on a metal surface whose threshold frequency is v₀. The kinetic energy of the emitted photoelectrons will be ______.

The work function of a photosensitive material is 4.0 eV. The longest wavelength of light that can cause photon emission from the substance is (approximately) ____________.

A simple pendulum performs simple harmonic motion about x = 0 with an amplitude A and time period T. The speed of the pendulum at x =A/2 will be ____________.

Which one of the following statements ts INCORRECT for stopping potential in photoelectric emission?

The velocities of a particle performing linear S.H.M are 0.13 m/s and 0.12 m/s, when it is at 0.12 m and 0.13 m from the mean position respectively. If the body starts from mean position, the equation of motion is ____________.

The mass and radius of earth is 'M_e' and 'R_e' respectively and that of moon is 'M_m' and 'R_m' respectively. The distance between the centre of the earth and that of moon is 'D'. The minimum speed required for a body (mass 'm') to project from a point midway between their centres to escape to infinity is ______.

Electrical conductivity of insulators is ______.

At absolute zero temperature, pure silicon behaves as ______.