Question

An electric field is produced by the very long, uniformly charged rod drawn above. If the strength of the electric field is E1 at a distance 1 r from the axis of the rod, at what distance from the axis is the field strength 1

Answer 1

Answer: hello the complete question is attached below

answer :

r2 = 4r1

Explanation:

Electric field strength = F / q

we will assume the rod has an infinite length

For an infinitely charged rod

E ∝ 1/ r

considering two electric fields E1 and E2 at two different locations as described in the question

E1/E2 = r1/r2 ----- ( 2 )

Calculate for r2 when E2 = E1/4

back to equation 2

E1 / (E1/4) = r1 / r2

∴ r2 = 4r1