Question

two point charges are .1m apart and their combined charge is 9Uc if they repel each other with force 18n find magnitude of charge

Answer 1

Q1 = 9 uC  and Q2 = 0.1 uC

Explanation:

Let Q1 and Q2 are two charges then according to given condition

Q1 + Q2 = 9uC     ………. (1)

Force = F = 18 N

Distance between charges = r = 0.1 m  

According to coulomb’s Law

F = K Q1 Q2/r2  

By putting values in above equation, we get  

Q1Q2 = 2 × 10-11   ………… (2)

By solving equation (1) and (2), we get

Q1 =  8.9 uC  and Q2 = 0.1 uC