HSC Science (Electronics) इयत्ता १२ वी - Maharashtra State Board Question Bank Solutions for Physics

Derive an expression for e.m.f. and current in terms of turns ratio

A transformer converts 240 V AC to 60 V AC. The secondary has 75 turns. The number of turns in primary are _______.

(A) 600

(B) 500

(C) 400

(D) 300

What is gamma decay?

Sample of carbon obtained from any living organism has a decay rate of 15.3 decays per gram per minute. A sample of carbon obtained from very old charcoal shows a disintegration rate of 12.3 disintegrations per gram per minute. Determine the age of the old sample given the decay constant of carbon to be 3.839 × 10⁻¹²per second.

The primary and secondary coils of a transformer each have an inductance of 200 x 10^-6 H. The mutual inductance between the windings is 4 x 10^-6 H. What percentage of the flux from one coil reaches the other?

A circular coil of 100 turns with a cross-sectional area of 1 m² is kept with its plane perpendicular to the magnetic field of 1 T. The magnetic flux linkage is ______.

Describe alpha, beta and gamma decays and write down the formulae for the energies generated in each of these decays.

Complete the following equation describing nuclear decay.

\[\ce{_88^226Ra->_2^4\alpha {+}}\] ______.

Complete the following equation describing nuclear decay.

\[\ce{_8^19O->e^- { +}}\] _____

Complete the following equation describing nuclear decay.

\[\ce{_90^228Th->\alpha { +}}\] _____

Complete the following equation describing nuclear decay.

\[\ce{_7^12N -> _6^12C {+}}\] ______

A particle executes S.H.M. of 2 cm. At the extreme position, the force is 4 N. What is the force at a point midway between mean and extreme positions?

State the formula for the frequency of S.H.M in terms of force constant. 

An ideal transformer has 100 turns in the primary and 250 turns in the secondary. The peak value of the AC is 28 V. The rms secondary voltage is nearest to ______ 

State the mathematical relation between a number of turns in the primary coil to a secondary coil in the step-up transformer. 

Distinguish between Step up and Step Down Transformer.

What is Transformer?

Explain step up and step down transformer?

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.

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