If an infinite line charge produces an electric field of 9×104N/C at a distance of 2 cm, what is the linear charge density?
Answer & explanation
Correct answer: option 2
E = \(\lambda \)/2\(\pi \)\(\epsilon_0 \) = 2\(\lambda \)/4\(\pi \)\(\epsilon_0 \)r
\(\lambda \) = 4\(\pi \)\(\epsilon_0 \)r E/2
r = 2 x 10-2 m ; E = 9 x 104 N/C
\(\lambda \) = 10-7 C/m