Question

two point charges +8q,_2qare located at 2 ends seprated by a distance of 3 meter .find the location of the point where the net electric field due to there 2 charges ix zero​

Answer 1

The electric field due to +8q is towards left and that due to −2q is towards right.

Electric field at a general point x=d (<0) is E=4πϵ01(−d28q+(L−d)22q)

If E=0, then d28q=(L−d)22q⇒(L−d)2d2=4

But, if d<0, then ∣d∣<∣L−d∣. Hence, no solution exists.

Consider the region between x=0 and x=L

The electric field due to +8q is towards right, and that due to −2q is towards right.

Hence, there is no point in(0,L) with zero electric field.

Consider the region between x=L and x=+∞

The electric field due to +8q is towards right and −2q is towards left.

Electric field at a general point x=d(>L) is given by E=4πϵ01(+d28q−(d−L)2