Match the symbols used in electric circuit diagrams to their functions.

a device that converts electric
energy into sound energy

a device that glows when it
receives current

a device that provides energy
to a circuit

a device that starts or stops
the flow of current

a device that converts electric
energy into sound energy

a device that glows when it
receives current

a device that provides energy
to a circuit

a device that starts or stops
the flow of current

The nuclear potential that binds protons and neutrons in the nucleus of an atom is often approximated by a square well. imagine a proton conned in an innite square well of length 105 nm, a typical nuclear diameter. calculate the wavelength and energy associated with the photon that is emitted when the proton undergoes a transition from the rst excited state (n 2) to the ground state (n 1). in what region of the electromagnetic spectrum does this wavelength belong?