The controller dish aerial has an effective area of 258 m2.
(c)
For the communication from part (b)
(i)
Determine the power received by the controller dish aerial. You may assume that the power transmitted by the satellite radiates uniformly in all directions.
[2]
(ii)
The actual power received by the controller dish aerial is 1.4 × 10−15 W. Suggest why this is different to the calculated power received.
[2]
(iii)
Calculate the rate at which microwave photons arrive at the controller dish aerial.
A boulder falls into a lake and ripples propagate radially outwards. Two boats on the surface of the water are in line with the source and perform the simple harmonic motion, bobbing up and down as the ripples pass by. The boats are separated by a distance of 45 m.
Two observations were recorded; the first ripple took 3.8 s to travel between the boats; the boats are completely out of phase.