HSC Science (Electronics) १२ वीं कक्षा - Maharashtra State Board Question Bank Solutions

Write a short note on Helical motion.

The moment of inertia (MI) of a disc of radius R and mass M about its central axis is ______.

Explain the change in internal energy of a thermodynamic system (the gas) by heating it.

Why a detergent powder is mixed with water to wash clothes?

The work done in bringing a unit positive charge from infinity to a given point against the direction of electric field is known as ______.

Define α.

Define β

Compare the rms speed of hydrogen molecules at 227°C with the rms speed of oxygen molecules at 127°C. Given that molecular masses of hydrogen and oxygen are 2 and 32 respectively.

Calculate the wavelength of the first two lines in the Balmer series of hydrogen atoms.

In U. C. M (Uniform Circular Motion), prove the relation `vec v = vec w xx vec r`, where symbols have their usual meanings.

A particle rotates in U.C.M. with tangential velocity V along a horizontal circle of diameter ‘D' . Total angular displacement of the particle in time 't' is..........

If sound waves are reflected from surface of denser medium, there is phase change of.......

The decay constant of radioactive substance is 4.33 x 10^-4 per year. Calculate its half life period.

State the principle on  which transformer works.

Explain the construction and working of the transformer. 

Derive an expression for ratio of e.m.f.s and currents in terms of number of turns in primary and secondary coil.

Determine the change in wavelength of light during its passage from air to glass. If the refractive index of glass with respect to air is 1.5 and the frequency of light is 3.5 x 10¹⁴ Hz, find the wave number of light in glass.

[Velocity of light in air c = 3 x 10⁸ m/s]

In biprism experiment, 10th dark band is observed at 2.09 mm from the central bright point on the screen with red light of wavelength 6400 A. By how much will fringe width change if blue light of wavelength 4800A is used with the same setting?

State the theorem of perpendicular axes about moment of inertia.

The power radiated by linear antenna of length T is proportional to........................

(λ= wavelength)

1. `lambda/ l`
2. `[lambda/l]^2`
3. `l/lambda`
4. `[l/lambda]^2`