1. The problem statement, all variables and given/known data A non conducting rod of length 2.2 m carries a negative charge of 3.8 ×10^-7 spread uniformly over it's length .What is the magnitude of electric field near the mid point of the rod at a perpendicular distance 3.6 mm from the rod? 2. Relevant equations E=λ/2πε0r 3. The attempt at a solution As it has been given that we have to calculate electric field near the mid point of the rod ;we can use the formula of infinite line charge for our rod of finite length (i.e 2.2m) using formula E=λ/2πε0r E=2λ/ 4πε0r PUTTING VALUES =9 ×10^9 ×2 ×3.8 ×10^-7/3.6 ×10^-3 =19 ×10^5 N/C but the answer should be 8.6 ×10^5 N/C where I am getting wrong?