When the Sun is directly overhead, the intensity of sunlight reaching the ground is about 1000 W/m^{2} 2 . The Earth has a radius of about 6400 km. What is the total power associated with sunlight shining on the Earth?

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?