HSC Science (Electronics) इयत्ता १२ वी - Maharashtra State Board Question Bank Solutions

Draw a neat labelled diagram of Ferry’s perfectly black body.

Define emissive power and coefficient of emmision of a body.

A metal sphere cools at the rate of 4°C / min. when its temperature is 50°C. Find its rate of cooling at 45°C if the temperature of surroundings is 25°C.

The resolving power of a telescope depends upon the ______.

Two copper spheres of radii 6 cm and 12 cm respectively are suspended in an evacuated enclosure. Each of them are at a temperature 15°C above the surroundings. The ratio of their rate of loss of heat is.................

1. 2:1
2. 1:4
3. 1:8
4. 8:1

Discuss the composition of two S.H.M.s along the same path having same period. Find the resultant amplitude and intial phase.

Discuss the composition of two S.H.M.s along the same path having same period. Find the resultant amplitude and intial phase.

The dimensions of emissive power are ______.

A pinhole is made in a hollow sphere of radius 5 cm whose inner wall is at temperature 727^oC. Find the power radiated per unit area. [Stefan’s constant σ = 5.7 x 10^-8 J/m² s K4 , emissivity (e) = 0.2]

Compute the temperature at which the r.m.s. speed of nitrogen molecules is 832 m/s. [Universal gas constant, R = 8320 J/k mole K, molecular weight of nitrogen = 28.]

If numerical aperture of a microscope is increased, then its ______.

The light from the Sun is found to have a maximum intensity near the wavelength of 470 nm. Assuming the surface of the Sun as a black body, the temperature of the Sun is _____________.

[Wien's constant b = 2 .898 x l0^{- 3}mK]

Derive an expression for kinetic energy, when a rigid body is rolling on a horizontal surface without slipping. Hence find kinetic energy for a solid sphere.

A metal ball cools from 64 ^°C to 50 ^°C in 10 minutes and to 42 ^°C in next 10 minutes. The ratio of rates of fall of temperature during the two intervals is _______.

Describe the construction of photoelectric cell.

The susceptibility of magnesium at 300 K is 2.4 x 10^-5. At what temperature will the susceptibility increase to 3.6 x 10^-5?

A network of four capacitors of 6 μF each is connected to a 240 V supply. Determine the charge on each capacitor.

A solid sphere of mass 1 kg rolls on a table with linear speed 2 m/s, find its total kinetic energy.

If a rigid body of radius ‘R’ starts from rest and rolls down an inclined plane of inclination
‘θ’ then linear acceleration of body rolling down the plane is _______.

1000 tiny mercury droplets coalesce to form a bigger drop. In this process, temperature of the drop _______ .

(A) increases

(B) may increase or decrease

(C) decreases

(D) does not change