5.1 a) Derive equation (5.16) from the bionomial distribution and Stirling's approximation.
5.2 Assume that photons are generated by a light source independently and randomly with an average rate N per second. How many must be counted by a photodetector per second to be able to determine the rate to within 1%? To within 1 part per million? How many watts do these cases correspond to for visible light?
For the spectrum of visible light I chose yellow light so 600. it wasn't the cleanest choice of numbers.
5.3 Consider an audio amplifier with a 20 kHz bandwidth. (a) If it is driven by a voltage source at room temperature with a source impedance of 10kΩ how large must the input voltage be for the SNR with respect to the source Johnson noise to be 20 dB?
