Question

Two charged small spheres are a distance R apart and exert an electrostatic force F on each other. If the distance is halved to R/5 , the force exerted on each sphere will be..

a) 25F
b) 5F
c) F/5
d) F/25

Answer 1

a) 25F

Step-by-step explanation:

Assuming that the two small spheres can be modeled as point charges, according to Coulomb's law, the magnitude of the electrostatic force is given by:

`F=(kq_1q_2)/(R^2)`

In this case, we have
`R'=(R)/(5)`:

`F'=(kq_1q_2)/(R'^2)\\F'=(kq_1q_2)/(((R)/(5))^2)\\F'=25(kq_1q_2)/(R^2)\\F'=25F`