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

An alternating voltage is given by E = 100 sin`(omega + pi/6)"V"`. The voltage will be maximum for the first time when is ______. [T = periodic time]

In half-wave rectifier, the RMS value of A.C. component of the wave is ____________.

A particle executes simple harmonic motion and is located at x = a, b, and c at times t₀, 2t_0, and 3t₀ respectively. The frequency of the oscillation is ______.

The work function of a metallic surface is 5.01 eV. The photoelectrons are emitted when light of wavelength 2000 Å falls on it. The potential difference applied to stop the fastest photoelectrons is [h = 4.14 x 10^-15 eV sec] ____________.

A thin semicircular conducting ring (PQR) of radius r is falling with its plane vertical in a horizontal magnetic field B, as shown in figure. The potential difference developed across the ring when its speed is v, is ____________.

Photoelectrons emitted from a metallic surface are initially ____________.

In photoelectric experiment, if both the intensity and frequency of the incident light are doubled, then the saturation of photoelectric current ______.

The forbidden energy band gap in conductors, semiconductors and insulators are `"E"_("g"_1), "E"_("g"_2) "and"  "E"_("g"_3)` respectively. The relation among them is ____________.

An important spectral emission line has a wavelength of 21 cm. The corresponding photon energy is (h = 6.62 x 10^-34 Js, c = 3 x 10⁸ m/s) ____________.

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 ______.

Light of wavelength `lambda` strikes a photo-sensitive surface and electrons are ejected with kinetic energy E. If the kinetic energy is to be increased to 2E, the wavelength must be changed to `lambda'` where ____________.

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 ______.

Gaussian surface cannot pass through discrete charge because ____________.

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 ______.

Threshold wavelength for lithium metal is 6250 Å. For photoemission, the wavelength of the incident light must be ______.

The threshold frequency for a certain photosensitive metal is v₀. When it is illuminated by light of frequency v = 2v₀, the maximum velocity of photoelectrons is v₀. What will be the maximum velocity of the photoelectrons when the same metal is illuminated by light of frequency 

v = 5v₀?