HSC Science (General) 12th Standard Board Exam - Maharashtra State Board Important Questions

Explain the construction of plane wavefront using Huygens’ principle.

The working of RADAR is based on ...............

a) resonance

b) speed of a star

c) Doppler effect

d) speed of rotation of sun

Determine the change in wavelenght of light during its passage from air to glass, if the refracrtive index of glass with respect to air is 1.5 and the frequency of light is 5 x 10¹⁴ Hz. Find the wave number of light in glass (velocity of light in air c = 3 X 10⁸ m/s)

Apparent frequency of the sound heard by a listener is less than the actual frequency of sound emitted by source. In this case _______.

(A) listener moves towards source

(B) source moves towards listener

(C) listener moves away from the source.

(D) source and listener move towards each other.

The minimum angular separation between two stars is 4 × 10⁻⁶ rad, if telescope is used to observe them with an objective of aperture 16 cm. Find the wavelength of light used.

State any four applications of Doppler effect

Explain Ampere’s circuital law.

The refractive indices of water and diamond are `4/3` and 2.42 respectively. Find the speed of light in water and diamond. (c = 3x10⁸ m/s)

A cyclotron is used to accelerate protons to a kinetic energy of 5 MeV. If the strength of magnetic field in the cyclotron is 2T, find the radius and the frequency needed for the applied alternating voltage of the cyclotron. (Given : Velocity of proton= `3xx10^7 m//s`)

Explain refraction of light on the basis of wave theory. Hence prove the laws of refraction

State Brewster’s law and show that when light is incident at polarizing angle the reflected and refracted rays are mutually perpendicular to each other.

Calculate the value of the magnetic field at a distance of 2 cm from a very long straight wire carrying a current of 5 A (Given: μ₀ = 4π × 10^-7 Wb/Am).

Choose the correct option.

A conducting thick copper rod of length 1 m carries a current of 15A and is located on the Earth's equator. There the magnetic flux lines of Earth's magnetic field are horizontal, with the field of 1.3 x 10^-4T, south to north. The magnitude and direction of the force on the rod, when it is oriented so that current flows from west to east are ______.

A very long straight wire carries a current of 5.2 A. What is the magnitude of the magnetic field at a distance 3.1 cm from the wire?

State any four applications of beats.

A strong magnetic field is applied to a stationary electron. Then the electron ______ 

A circular loop of radius 0.0157 m carries a current 2 A. The magnetic field at the centre of the loop is ______  

What is Solenoid?

A solenoid of length 50 cm of the inner radius of 1 cm and is made up of 500 turns of copper wire for a current of 5 A in it. What will be the magnitude of the magnetic field inside the solenoid? 

Explain the construction and working of the Moving coil Galvanometer.