HSC Science (General) १२ वीं कक्षा - Maharashtra State Board Important Questions for Physics

An electron in an atom is revolving around the nucleus in a circular orbit of a radius of 5.3 x 10^-11 m, with a speed of 2 x 10⁶ m/s. Find the resultant orbital magnetic moment and angular momentum of the electron. [e = 1.6 x 10^-19 C, m_e= 9.1 x 10^-31 kg]

A magnet of magnetic moment 3Am² weighs 75 g. The density of the material of the magnet is 7500 kg/m³. what is magnetization? 

What is magnetic susceptibility?

State SI unit of Magnetization.

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

Explain why the inductance of two coils connected in parallel is less than the inductance of either coil.

Why and where are eddy currents are undesirable? How are they minimized? 

Define self-inductance.

The magnetic flux through a loop varies according to the relation Φ = 8t² + 6t + 2, Φ is in milliweber and t is in second. What is the magnitude of the induced emf in the loop at t = 2 seconds?  

Explain step up and step down transformer?

Determine the motional emf induced in a straight conductor moving in a uniform magnetic field with constant velocity on the basis of Lorentz force.

The primary of a transformer has 40 turns and works on 100 V and 100 W. Find a number of turns in the secondary to step up the voltage to 400 V. Also calculate the current in the secondary and primary.

Using Ampere's law, obtain an expression for the magnetic induction near a current-carrying straight infinitely long wire. 

Describe the construction and working of a transformer with a neat labelled diagram.

In a series LCR circuit, the phase difference between the voltage and the current is 45°. Then the power factor will be ______.

State any two characteristics of a series LCR AC resonance circuit.

Find the current in a circuit consisting of a coil and a capacitor in series with an A.C source of 110V (r.m.s.), 60Hz. The inductance of a coil is 0.80 H and its resistance is 50Ω. The capacitance of a capacitor is 8µF. 

A radio can tune over the frequency range of a portion of the MW broadcast band (800kHz -1200kHz). If its LC circuit has an effective inductance of 200mH, what must be the range of its variable condenser? 

If the frequency of incident light falling on a photosensitive material is doubled, then the kinetic energy of the emitted photoelectron will be ______.

Which one of the following particles cannot be accelerated by a cyclotron?

(A) Electrons

(B) Protons

(C) Deuterons

(D) α- particles