Electromagnetic Waves — Physics STD 12 Science — Question

What is called critical angle?

Two equal balls having equal positive charge ‘q’ coulombs are suspended by two insulating strings of equal length. What would be the effect on the force when a plastic sheet is inserted between the two?

A signal of 5 kHz frequency is amplitude modulated on a carrier wave of frequency 2 MHz. What are the frequencies of the side bands produced?

A capacitor has capacitance C. Is this information sufficient to know what maximum charge the capacitor can contain? If yes, what is this charges? If no, what other information is needed?

In long range transmission, why micro waves are better carrier than radio waves?

What is a photon?

When a charged particle moves in a magnetic field normally; what quantity changes the particle’s speed, particle’s energy, path of motion of the particle?

To observe the photoelectric effect, the frequency of incident light should be greater than which frequency?

Suppose a charged particle moves with a velocity v near a wire carrying an electric current. A magnetic force, therefore, acts on it. If the same particle is seen from a frame moving with velocity v in the same direction, the charge will be found at rest. Will the magnetic force become zero in this frame? Will the magnetic field become zero in this frame?