Two point charges and are separated by a distance in vacuum and exert a force on each…

PHYSICS · Single correct · A Level · Physics · Fields and their consequences · Fields and their consequences

Problem

Two point charges

q

and

4q

are separated by a distance

d

in vacuum and exert a force

F

on each other. What will be the force between the same charges when they are placed

2d

apart in a medium of relative permittivity

\varepsilon_{r}=5

? (a)

\dfrac{F}{4}

(b)

\dfrac{F}{5}

(c)

\dfrac{F}{20}

(d)

\dfrac{F}{10}