Five point charges, each of value +q coul, are placed on five vertices of a regular hexagon of isde L meters. The magnitude of the force on the point charge of value -q coul, placed at the centre of the hexagen is…………….

Answer

A, B, D

Explanation

`(a//2)/r=cos60^@=1/2`
`:. a=r`
`q_1=q_2=….=q_5=q`
Net force on -q is only due to `q_3` because force due to `q_1` and due to `q_4` are equal and opposite so cancel each other. Similarly forces due to `q_2` and `q_5` also cancel each other. Hence, the net foce on `-q` is
` F=1/(4piepsilon_0).((q)(q))/r^2` (towards `q_3`)
or `F=1/(4piepsilon_0).q^2/r^2`