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

Prove the law of conservation of energy for a particle performing simple harmonic motion.Hence graphically show the variation of kinetic energy and potential energy w. r. t. instantaneous displacement.

Explain how moving coil galvanometer is converted into a voltmeter. Derive the necessary formula.

A rectangular coil of a moving coil galvanometer contains 100 turns, each having area
15 cm². It is suspended in the radial magnetic field 0.03 T. The twist constant of suspension
fibre is 15 x 10^-10 N-m/degree. Calculate the sensitivity of the moving coil galvanometer.

Within the elastic limit, find the work done by a stretching force on a wire.

A set of 12 tuning forks is arranged in order of increasing frequencies. Each fork produces Y beats per second with the previous one. The last is an octave of the first. The fifth fork
has a frequency of 90 Hz. Find Y and frequency of the first and the last tuning forks.

If the Earth completely loses its gravity, then for any body _______.

(A) both mass and weight become zero.
(B) neither mass nor weight become zero.
(C) weight becomes zero but not the mass.
(D) mass becomes zero but not the weight.

Draw a neat, labeled diagram showing different layers of the Earth’s atmosphere.

The refractive indices of glass and water w.r.t. air are 3/2 and 4/3 respectively. Determine the refractive index of glass w.r.t. water.

A sonometer wire vibrates with three nodes and two antinodes, the corresponding mode of vibration is ...................

a) First overtone

b) Second overtone

c) Third overtane

d) Fourth overtone

The fraction of the total current passing through the galvanometer is ............ .

a) `S/(S+G)`

b) `G/(S+G)`

c) `(S+G)/G`

d) `(S+G)/S`

A moving coil galvanometer has a resistance of 25Ω and gives a full scale deflection for a current of 10mA. How will you convert it into a voltmeter having range 0 - 100 V?

The kinetic energy of nitrogen per unit mass at 300 K is 2.5 × 106 J/kg. Find the kinetic energy of 4 kg oxygen at 600 K. (Molecular weight of nitrogen = 28, Molecular weight of oxygen = 32)

A galvanometer has a resistance of 16Ω. It shows full scale deflection, when a current of 20 mA is passed through it. The only shunt resistance available is 0.06  which is not appropriate to convert a galvanometer into an ammeter. How much resistance should be connected in series with the coil of galvanometer, so that the range of ammeter is 8 A?

The refractive indices of water for red and violet colours are 1.325 and 1.334 respectively.
Find the difference between the velocities of rays for these two colours in water. (c = 3 × 10⁸ m/s)

A ray of light passes from a vacuum to a medium of refractive index (μ). The angle of
incidence is found to be twice the angle of refraction. The angle of incidence is _______.

A) `cos^(-1)(mu/2)`

B) cos⁻¹(μ)

C)  `2 cos^(-1) (mu/2)`

D) `2 sin^(-1) (mu/2)`

Show that only odd harmonics are present in an air column vibrating in a pipe closed at one end.

A stretched wire emits a fundamental note of frequency 256 Hz. Keeping the stretching force constant and reducing the length of wire by 10 cm, the frequency becomes 320 Hz. Calculate the original length of wire.

Explain two types of diffraction of light.

State two uses of Polaroid.

The glass plate of refractive index 1.732 is to be used as a polarizer, its polarising angle is _______.