You take a picture with a f-number of f/4 and a shutter duration of 1/60 seconds. You change the f-number to f/2.8 and the shutter duration to 1/240 seconds. The light intensity reaching the sensor has changed by what factor?

Aparticle of mass m is placed in a one-dimensional box of length l. the box is so small that the particle’s motion is relativistic, so that e p2/2m is not valid. (a) derive an expression for the energy levels of the particle using the relativistic energy–momentum relation and the quantization of momentum that derives from connement. (b) if the particle is an electron in a box of length l 1.00 1012 m, nd its lowest possible kinetic energy. by what percent is the nonrelativistic formula for the energy in error?