An electron and a proton are a distance r 45 109 m apart H

An electron and a proton are a distance r = 4.5 × 10-9 m apart. How much energy is required to increase their separation by a factor of 8?

Solution

PE1 + energy required to separate = PE2

=> -K1q1q2/r1 + energy required to separate =  -K1q1q2/r2

=>  energy required to separate = K1q1q2/r1 -  K1q1q2/r2 = (9*10^9*(1.6*10^-19)^2*7)/(8*4.5*10^-9)

= 4.48*10^-20 Joule