(a(i))[1]
State the angle of incidence at point P.
(a(ii))[2]
Draw the normal and show the angle of incidence at point R. Label the angle of incidence.
(a(iii))[2]
State two conditions that must be satisfied for no light to refract from the glass into the air at point Q.
(b(i))[1]
Information is sent over the internet by pulses of visible light in long, thin glass fibres and by electrical signals in copper wires. State the name of one other type of electromagnetic radiation used to transmit information through long, thin glass fibres.
(b(ii))[2]
Suggest two advantages of glass fibres over copper wires for transmitting information from the internet.