Recent content by JonnyW

Question the third: Energy of the photon is 5x10^(-19) J Energy of electron = it's momentum squared over twice it's mass, therefore E = (9.5x10^(-25))^2 / 2x9.1x10^(-31) = 4.96x10^(-19) J which is as near as damn it to the energy of the photon. Energy of a photon, E = hf, where c = fw...

The Moon is actually moving away from us at about 4cm per year

'Actually, people can also float inside airplanes that are much closer to the ground. Perhaps there is a better explanation?' That would be when the plane is accelerating towards Earth faster than 9.81 ms^-2 and this can only be done for short periods of time. The effect is that you are...

If a telescope is 2 time bigger in diameter then you can see object 4 times fainter, but does that mean that object appear 4 times brighter?