A meter bridge is used to determine the resistance of an unknown wire by measuring the balance point length I. If the wire is replaced by another wire of same material but with double the length and half the thickness, the balancing point is expected to be. 1) 1 8l 2) 1 4l 3) 8l 4) 16l

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?