Why isn't iron used to make coin

Hen a gfci receptacle device is installed on a 20-ampere branch circuit (12 awg copper), what is the minimum volume allowance (in cubic inches) required for conductor fill for each conductor in the outlet box?

Positrons are spontaneously emitted from the nuclei of

Consider a system with two masses that are moving away from each other. why will the kinetic energy differ if the frame of reference is a stationary observer or one of the masses?