Question

ln the figure ,if net force on Q is zero then value of Q/Q is

Answer 1

$2 \sqrt{2}$

Answer 2

(The diagram is missing in the question it is attached below in the answer)

Given :

Length of side of a square = r

Charge 1 (q₁) = Q

Charge 2 (q₂) = q

To Find :

The value of the ratio Q/q = ?

Solution :

• As the net force acting on Q is zero, The charges Q and q should be of opposite sign

• Net force on Q = Force due to  q - Force due to  Q = 0

• Force due to charge q = Force due to charge Q  

         $\sqrt{(\frac{kQq}{r^{2} } )^{2}+ (\frac{kQq}{r^{2} } )^{2}} = {\frac{kQQ}{(\sqrt{2r})^{2} } }$

         $\sqrt{2(\frac{kQq}{r^{2} } )^{2}} = {\frac{kQQ}{(\sqrt{2r})^{2} } }$

         $2\sqrt{2}Qq = Q^{2}$

         $\frac{Q}{q} =2\sqrt{2}$

The value of the ratio Q/q is 2√2