The sides of two solid cubes of the same material are \(l\) and \(3l\) respectively. The ratio of their resistances will be:
If \( V_L, V_R, V_C \), and \( V_O \) are readings of AC voltmeter across the inductor, resistor, capacitor, and source respectively in a certain L-C-R circuit, then:
Which of the following laws of conservation holds in Einstein's photoelectric equation?
If the radius of the nucleus of \(^{13} \text{Al}^{27}\) is 3.6 fermi, then the radius of the nucleus of \(^{52} \text{Te}^{125}\) is:
The unit of magnetic field is
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 \( q_0 \).
Compare features of p-type and n-type semiconductors. Draw circuit diagram of half-wave rectifier of p-n junction diode and explain it.
What is atomic model of magnetism? Differentiate between paramagnetic, diamagnetic, and ferromagnetic substances on this basis. Also, give one example of each.
By drawing a ray diagram, explain the formation of image in a compound microscope. Establish the formula for magnifying power for it.
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.
What are electromagnetic waves? Draw their propagation diagram. Show the electric field amplitude and magnetic field amplitude in the propagation diagram.
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?