HSC Science (General) 12th Standard Board Exam - Maharashtra State Board Question Bank Solutions for Physics

Draw a neat labelled diagram for Ferry's perfectly black body.

Let 'p'  and 'E' denote the linear momentum and energy of emitted photon respectively. If the wavelength of incident radiation is increased ___ .
(a) both p and E increase
(b) p increases and E decreases
(c) p decreases and E increases
(d) both p and E decrease.

In case of transistor oscillator, to obtain sustained oscillations, the product of voltage gain without feedback and feedback factor should be __________.

Show graphical representation of energy distribution spectrum of perfectly black body.

The wavelength range of thermal radiation is

(A) from 4000 Å to 7000 Å

(B) from 7700 Å to 4 x 10⁶ Å

(C) from 106 Å to 10⁸ Å

(D) from 4 x 10^-12 Å to 4 x 108 Å

If the difference in velocities of light in glass and water is 2.7 x 10⁷ m/s, find the velocity of light in air. (Refractive index of glass = 1.5, Refractive index of water = 1.333)

When electron in hydrogen atom jumps from second orbit to first orbit, the wavelength of radiation emitted is λ. When electron jumps from third orbit to first orbit, the wavelength of emitted radiation would be _______.

(A)`27/32lambda`

(B)`32/27lambda`

(C)`2/3lambda`

(D)`3/2lambda`

Find the wavelength at which a black body radiates maximum energy, if its temperature is 427°C.
(Wein’s constant b = 2.898 × 10^-3 mK)

(A) 0.0414 × 10^-6m

(B) 4.14 × 10^-6m

(C) 41.4 × 10^-6m

(D) 414 × 10^-6m

If A.C. voltage is applied to a pure capacitor, then voltage across the capacitor _____________.

State and prove Kirchoff’s law of heat radiation.

Find the ratio of longest wavelength in Paschen series to shortest wavelength in Balmer series.

The speed limit for a vehicle on road is 120 km/ hr. A policeman detects a drop of 10% in the pitch of horn of a car as it passes him. Is the policeman justified in punishing the car driver for crossing the speed limit? (Given: Velocity of sound= 340 m/s)

In hydrogen atom Balmer series is obtained when the electron jumps from ............ .

(a) higher orbit to first orbit

(b) first orbit to a higher orbit

(c) higher orbit to the second orbit

(d) second orbit to a higher orbit

What is de Broglie wavelength of an electron accelerated through 25000 volt?

Light of wavelength 3000Å falls on a metal surface having work function 2.3 eV. Calculate the maximum velocity of ejected electrons

(Planck's constant h = 6.63 x 10^-34 J.s., Velocity of light c = 3 x 10⁸ m/s, mass of an electron = 9.1 x 10^-31 kg)

With the help of a neat diagram, describe the construction and working of van de Graff generator.

Explain black body radiation spectrum in terms of wavelength

Define the coefficient of self-induction.

Write the SI unit and dimention of of co-efficient of self induction

What is perfectly black body ? Explain Ferry’s black body.