List of top Physics Questions

Using Gauss' theorem, derive an expression for electric field intensity due to a uniformly charged hollow sphere (shell) at a point outside the shell and at a point inside the shell.
Write the assumptions, sign conventions and then derive the mirror formula for concave mirror.
What is diffraction of light? Explain diffraction at a single slit and deduce the expression for the width of its central maxima.
Explain Biot-Savart's law for a small current-carrying conductor.
Define the coefficient of self-induction and find an expression for it for a solenoid.
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?
A proton enters into a magnetic field of intensity \( 5 \times 10^{-2} \) Tesla with velocity \( 10^5 \, \text{m/s} \) at an angle of 30° with the field. Calculate the magnitude of force acting on the proton due to this field.
With the help of a circuit diagram, explain the V-I characteristics of a p-n junction in reverse biasing.
Write down at least three properties of nuclear force.
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.
Find the focal length of the combination of two thin lenses in contact.
With the help of a circuit diagram, explain the V-I characteristics of a p-n junction in reverse biasing.
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.
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 \( \Omega \).
What is resistance? Define SI unit of resistance.
Calculate the Coulomb’s force between proton and electron separated by a distance of \( 0.8 \times 10^{-15} \) m.
What is displacement current?
What are the factors which reduce the efficiency of a transformer?
Derive an expression for magnetic force. How is the direction of magnetic force determined?
The size of the mirror does not affect the nature of the image. (T/F)
The density of nuclear matter is independent of the size of the nucleus. (T/F)
Why can’t two equipotential surfaces intersect each other?
Calculate the de-Broglie wavelength for electrons moving with speed of \( 10^5 \, \text{m/s} \).
Define threshold wavelength and frequency.