State Gauss's Law in electrostatics. Using it (i) find electric field due to a point source charge \( q \) and (ii) deduce Coulomb's law between source charge \( q \) and test charge \( q_0 \).
What is atomic model of magnetism? Differentiate between paramagnetic, diamagnetic, and ferromagnetic substances on this basis. Also, give one example of each.
What is Bohr's quantum condition postulate? How is it explained by de Broglie? What are the shortcomings of Bohr's atomic model?
Obtain the expression for capacity of a parallel plate capacitor. How will the capacity of the capacitor be increased?
Establish the relation between resistances of arms of Wheatstone bridge in balanced condition.
Determine the nature of force acting between two parallel current-carrying conductors when: (i) Current is in the same direction in conductors, (ii) Current is in the opposite direction in conductors.
Define interference. Mention the condition for constructive and destructive interference.
A plastic ball \( P \) of mass \( 3.2 \times 10^{-15} \, \mathrm{kg} \) is suspended between two horizontal parallel charged plates in a balanced state. How many electrons on the ball will be increased or decreased? \((g = 10 \, \mathrm{m/s}^2)\)
Explain nuclear fission and nuclear fusion with examples.
Discuss the significance of displacement current and find the phase difference between it and the conduction current.
If a thin prism of glass is immersed in water, then prove that the minimum deviation produced by the prism becomes one-fourth with respect to air. Given refractive index of glass with respect to air = \( \frac{3}{2} \) and that of water with respect to air = \( \frac{4}{3} \).
What is the effect on range and sensitivity of an ammeter when the value of its shunt resistance increases?
The atomic mass of \( ^{16}O \) is 16.0000 amu. Calculate its binding energy per nucleon. Mass of electron = 0.00055 amu, mass of proton = 1.007593 amu, mass of neutron = 1.008982 amu, and 1 amu = 931 MeV.
Explain the operation of p-n junction diode in forward bias.
A double concave lens has to be made from crown glass. How much should the radii of surfaces of lens be kept to make the power of lens -2.5 D? Refractive index of crown glass is 1.65.
Define the mass defect and binding energy of nucleus.
Between radio waves and microwaves, which one has a higher frequency?
How much charge is there on a hole? Draw the circuit symbol of p-n junction diode.
In hydrogen atom, what is the ionization potential of the electron in the ground state?
Find the ratio of the focal length of lens in air and that of lens when it is immersed in liquid.
Force of 80 Newton works between two point charges placed at a fixed distance apart in air. When these charges are placed at the same distance apart in a dielectric medium, then the force of 8 Newton works on it. The dielectric constant of the medium will be:
The power consumed in alternating current in a circuit containing only a capacitor will be: