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

In a series LCR circuit at resonance, the applied e.m.f. of the source and current in the circuit are ______.

Light of frequency 2 times the threshold frequency is incident on a photo sensitive material. If the frequency is made `1/3`rd and intensity is doubled then the photocurrent will ______.

When wavelength of incident radiation on the metal surface is reduced from 'λ₁' to 'λ₂', the kinetic energy of emitted photoelectrons is tripled. The work function of the metal is ______.
(h = Planck's constant, c =velocity of light)

When light of wavelength 'λ' is incident on a photosensitive surface, the stopping potential is 'V'. When light of wavelength '3λ' is incident on the same surface, the stopping potential is `"V"/6`. Threshold wavelength for the surface is _______.

The photo electric effect to take place for a metal, the minimum frequency required is 5.792 × 10¹⁴ Hz. A light of wavelength 6000 Å is incident on that metal surface. What is the corresponding frequency of light and will there be photoelectric emissions? [velocity of light = 3 × 10⁸ m/s]

Photoelectrons are emitted from a photosensitive surface for the light of wavelengths λ₁ = 360 nm and λ₂ = 600 nm. What is the ratio of work functions for lights of wavelength 'λ₁' to 'λ₂'?

When a surface 1 cm thick is illuminated by light of wavelength 'λ', the stopping potential is 'V₀'. When the same surface is illuminated by light of wavelength '3λ', the stopping potential is `"V"_0/6`. The threshold wavelength for the metallic surface is ______.

In hydrogen spectnun, the wavelengths of light emited in a series of spectral lines is given by the equation `1/lambda = "R"(1/3^2 - 1/"n"^2)`, where n = 4, 5, 6 .... And 'R' is Rydberg's constant.
Identify the series and wavelenth region.

Angular speed of an electron in the ground state of hydrogen atom is 4 × 10¹⁶ rad/s. What is its angular speed in 4^th orbit?

Ratio of centripetal acceleration for an electron revolving in 3^rd orbit to 5^th orbit of hydrogen atom is ______.

Magnetic material can be easily magnetized if magnetic susceptibility is ______.

If a magnetic field is applied to a liquid in one arm of a narrow U-tube, the liquid level in that arm is lowered. The liquid in U-tube arm is ______.

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]

An electron of mass 'm' is rotating in first Bohr orbit of radius 'r' in hydrogen atom. The orbital acceleration of the electron in first orbit (h = Planck's constant).

In Bohr model, speed of electron in nth orbit of hydrogen atom is ______. (b = Planck's constant, n = principal quantum number, ∈₀ is the permittivity of free space, e = electronic charge)

Two waves are represented by the equations `"y"_1, = "a sin" (omega"t"+ "kx" + 0.57)` m and `"y"_2, = "a cos" (omega"t"+ "kx")` m, where x is in metre and t in second. The phase difference between them is ____________.

The distance covered by a particle undergoing SHM in one time period is (amplitude = A) ____________.

Which of the following represents the acceleration versus displacement graph of SHM?

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