(a(i))[1]
State the principal region of the electromagnetic spectrum to which the wave belongs.
(a(ii))[2]
Calculate the wave's frequency, in THz.
(b(i))[1]
The light waves leaving the two slits are coherent. State what is meant by coherent.
(b(ii))[3]
Calculate the slit separation, $a$.
(c(i))[1]
Calculate the difference between the distances from each slit to the centre of fringe Q (the path difference).
(c(ii))[1]
State the phase difference between the light waves at the centre of fringe R.