Question

How many excess electrons must be placed on each of two small spheres spaced 3 cm apart if the force of repulsion between the spheres is to be 10^-19?.​

Answer 1

Answer:

ANSWER

Force between the two electrons,

F=

4πϵ

0

1

×

d

2

(ne)(ne)

or n

2

=

e

2

F×4πϵ

0

×d

2

n

2

=

(1.6×10

−19

)

2

10

−19

×

9×10

9

1

×(3×10

−2

)

2

=(625)

2

or n=625

∴ The number of electrons placed on each of the sphere =625.