(a)[3]
State three conditions that have to be satisfied for maxima to be produced in an interference pattern formed by two sources of microwaves.
(b)[3]
A microwave source $M$ produces microwaves with frequency $12\,\text{GHz}$. Show that the wavelength of the microwaves is $0.025\,\text{m}$.
(c)
Two slits $S_1$ and $S_2$ are positioned in front of the microwave source $M$ from (b), as shown in Fig. 5.1. The distances $S_1O$ and $S_2O$ are equal. A microwave detector is then moved from $O$ to $P$. The distance $S_1P$ is $0.75\,\text{m}$ and the distance $S_2P$ is $0.90\,\text{m}$.
(d)[2]
The microwave source M is replaced by a source of coherent light. State two changes that must be made to the slits in Fig. 5.1 so that an interference pattern can be observed.