Electromagnetic Waves — Physics STD 12 Science — Question

What is the value of electrical conductivity of a semiconductor at absolute zero?

What effect does the dielectric medium have on the capacitance of a capacitor?

Answer the following question:
A magnetic field that varies in magnitude from point to point but has a constant direction (east to west) is set up in a chamber. A charged particle enters the chamber and travels undeflected along a straight path with constant speed. What can you say about the initial velocity of the particle?

Two blocks A and B of mass m_A and m_B respectively are kept in contact on a frictionless table. The experimenter pushes the block A from behind so that the blocks accelerate. If the block A exerts a force F on the block B, what is the force exerted by the experimenter on A?

Answer the following questions:
Why is diamagnetism, in contrast, almost independent of temperature?

What is the relation between produced magnetic field at the center of a circular current carrying coil and its radius?

Would you prefer a voltmeter or a potentiometer to measure the emf of a battery?

Find the excess pressure inside:

1. A drop of mercury of radius 2mm.
2. A soap bubble of radius 4mm.
3. An air bubble of radius 4mm formed inside a tank of water. Surface tension of mercury, soap solution and water are 0.465N/m, 0.03N/m and 0.076N/m respectively.

The speeds of red light and yellow light are exactly same:

1. In vacuum but not in air.
2. In air but not in vacuum.
3. In vacuum as well as in air.
4. Neither in vacuum nor in air.