Two small nonconducting spheres have a total charge of 94.0 μC . Part A When placed 31 cm apart, the force each exerts on the other is 11.5 N and is repulsive. What is the charge on each?

Q1,Q2=

Part B

What if the force were attractive?

Q1,Q2=

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?