Answer:
A
Explanation:
The electric field = 1000N/C
Using the formula
F = q/4πeD^2 where F is the force experience by a charge body brought from infinity to D and e is the field constant in C/N.m^2 and D is the distance from the uniform field
1000 = q/4πeD^2
Make q subject of the formula
1000*(4πeD^2) = q
If the force changes to 2000 then equation changes to:
2000 = q /4πeD1^2 where D1 is the new distance
Substitute q in equation 2
2000 = 1000*(4πeD^2) / 4πeD1^2
Cancel 4πe
2000 = 1000 * D^2 / D1^2
Cross multiply and make D1^2 subject of the formula
D1^2 = 1000D^2/ 2000
D1^2 = D^2/2
Take square root of both side
D1 = √(D^2/2) = D / √2
