Question

Given that the mass of an electron is 9.1 x 10^-28 grams and the charge on an electron is 1.6 x 10^-19 Coulombs, calculate the voltage required to lift an electron 5 cm.

not quite sure how to do this.

Answer 1

Potential energy gain = q V = m g h

V = m g h/q

V = 9.1 * 10^-28*10^-3 * 9.8 *5*10^-2 / 1.6*10^-19

Answer 2

Hi Damon .. where did the 10^-3 come from? .. I understand the 9.8 is gravity and the 5 is 5 cm

Answer 3

Damon used kg for mass and meters for distance. Those units go with the 9.8 m/s^2 for g. The 10^-3 and 10^-2 are conversion factors from grams and cm.