What is a disadvantage of having lots of turns in an elctromagnet

Imagine you had to physically add electrons, one at a time, to a previously neutral conductor. you add one electron very easily, but the second electron requires more work. in your initial post to the discussion, explain why this is. also, what happens to the work needed to add the third, fourth, fifth, and subsequent electrons

The friction of the water on a boat produces an acceleration of -10. m/s2. if the boat is traveling at 30. m/s and the motor is shut off, how long it take the boat to slow down to 5.0 m/s?

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?