Q 12.11 In Bohr’s atomic model of hydrogen atom, the electron is in an orbit around the nuclear proton at a distance of 5.29 * 10(-11) m with a speed of 2.18 8 10(6) m/s. (a) The electric potential that a proton exerts at this distance. (b) Total energy of the atom in eV. (c) …

Q 12.12 The electrostatic flash attachment for a camera contains a capacitor for storing energy used to produce the flash. In one such unit, the potential difference between the plates of a 750 micro Farad capacitor is 330 Volt. Determine the energy that is used to produce the flash.

Q 12.13 A capacitor has a capacitance of 2.5 * 10(-8) Farad. In the changing process, electrons removed from one plate and placed on the other one. When the potential difference between the plates is 450 volt, how many electrons have been transferred? (e = 1.60 * 10(-19) Coulomb)