Answer to Question #208738 in Electricity and Magnetism for Cleopatra

Question

Two small spheres , with a charge of Q1 on the other sphere and a charge Q2 on the other sphere ,have a distance r between their centers so thata they exert a force F on each other.What will happen to the force force F between them if one of the charges is doubles?

If bothe the charges are doubled?

Answer 1

Gives

Charge $=Q_1$

Charge=$Q_2$

$F=\frac{kQ_1Q_2}{r^2}=F_1$

When one charge is doubled

$Q'_1=2Q_1$

$F_2=2\frac{kQ_1 Q_2}{r^2}=2F_1$

Both force are double

$Q''_1=2Q_1$

$Q''_2=2Q_2$

$F_3=\frac{kQ''_1Q''_2}{r^2}$

$F_3=4\frac{kQ_1Q_2}{r^2}=4F_1$