Question

Two charged particle of charge $+2q$ & $-q$ are kept at some distance .A particle of charge $+2q$ exerts a force $F$ on a particle of charge $-q$. Find out the force exerted by the particle of charge $-q$ on the particle of charge $+2q$?

• A. $1/2F$
• B. $0$
• C. $2F$
• D. $F$
• E. $-F$

Answer 1

The correct option is E $-F$

As the given charges are opposite ,there will attract each other.it means charge $+2q$ pulls the charge $-q$ towards itself and same activity will be done by charge $-q$ ,they exert force on each other in opposite direction direction.

now , electrostatic force between them

$F=\frac{1}{4\pi \epsilon }\frac{2q\times q}{r^2}$

that is the force exerted by one charge on another therefore $-q$ will exert equal force on charge $+2q$ but in opposite direction i.e $-F$