List of practice Questions

A wire is cut across a flux of \( 0.2 \times 10^{-2} \) weber in 0.12 seconds. What is the e.m.f. induced in the wire?
Find the focal length of the combination of two thin lenses in contact.
Two lenses, one diverging of power 2D and the other converging of power 6D are combined together. Calculate the focal length and power of combination.
Write down at least three properties of nuclear force.
With the help of a circuit diagram, explain the V-I characteristics of a p-n junction in reverse biasing.
With the help of a circuit diagram, explain the V-I characteristics of a p-n junction in reverse biasing.
Derive an expression for the potential energy of a charged capacitor.
Find the total resistance of a circuit in which three resistances are connected in series.
Calculate the Coulomb’s force between proton and electron separated by a distance of \( 0.8 \times 10^{-15} \) m.
What is resistance? Define SI unit of resistance.
Calculate the resistivity of the material of a conductor of length 3 m, area of cross section \( 0.2 \, \text{mm}^2 \) having a resistance of 2 \( \Omega \).
Derive an expression for magnetic force. How is the direction of magnetic force determined?
What are the factors which reduce the efficiency of a transformer?
What is displacement current?
The density of nuclear matter is independent of the size of the nucleus. (T/F)
The size of the mirror does not affect the nature of the image. (T/F)
Define threshold wavelength and frequency.
Calculate the de-Broglie wavelength for electrons moving with speed of \( 10^5 \, \text{m/s} \).
Write an expression for mass defect.
Why can’t two equipotential surfaces intersect each other?
Wheatstone bridge is used to measure:
The ultimate individual unit of magnetism in any magnet is:
The laws of electromagnetic induction have been used in the construction of:
Diffraction of light is the phenomenon of bending of light around the corners of an aperture in its path. (T/F)
The strength of a bar magnet is maximum at its center. (T/F)