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

Distinguish between diamagnetic and paramagnetic substances.

Distinguish between diamagnetic and paramagnetic substances.

When a resistance of 12 ohm is connected across a cell, its terminal potential difference is balanced by 120 cm length of potentiometer wire. When the resistance of 18 ohm is connected across the same cell, the balancing length is 150 cm. Find the balancing length when the cell is in open circuit. Also calculate the internal resistance of the cell.

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

Two gases exert pressure in the ratio 3: 2 and their densities are in the ratio 2: 3, then the ratio of their R.M.S. velocities is ...........

State Kepler's laws of planetary motion.

A meter gauge train is heading north with speed 54 km/hr in earth's magnetic field 3 x 10^-4T. The e.m.f. induced across the axle joining the wheels is ..........

(a) 0.45 mV

(b) 4.5 mV

(c) 45 mV

(d) 450 m V

A meter gauge train is heading north with speed 54 km/hr in earth's magnetic field 3 x 10^-4T. The e.m.f. induced across the axle joining the wheels is ..........

(a) 0.45 mV

(b) 4.5 mV

(c) 45 mV

(d) 450 m V

A particle executing linear S.H.M. has velocities v₁ and v2 at distances x₁ and x₂ respectively from the mean position. The angular velocity of the particle is _______

Draw a well labelled diagram of photoelectric cell.

Explain the observations made by Hertz and Lenard about the phenomenon of photoelectric
emission.

The magnetic susceptibility of annealed iron at saturation is 4224. Find the permeability of
annealed iron at saturation. (μ₀ = 4Π × 10⁻⁷ SI unit)

The magnetic susceptibility of annealed iron at saturation is 4224. Find the permeability of
annealed iron at saturation. (μ₀ = 4Π × 10⁻⁷ SI unit)

The number of photoelectrons emitted _______.

(A) varies inversely with frequency

(B) varies directly with frequency

(C) varies inversely with intensity

(D) varies directly with intensity

The width of depletion region of p-n junction diode is _______.

(A) 0.5 nm to 1 nm

(B) 5 nm to 10 nm

(C) 50 nm to 500 nm

(D) 500 nm to 1000 nm

State its any ‘two’ uses of photodiode.

Define coefficient of mutual induction. 

Explain the phenomenon of mutual induction.

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.