A plastic rod of length 2.2m and radius 3.6 mm carries a negative charge of `3.8xx10^(-7) C` spread uniformly over its surface. What is the electric field near the mid-point of the rod, at a point on its surface?

Explanation

Rod is assumed to be infinite length
So `E = ( lambda) /(2 piepsilon_(0)f)= ( 2lambda)/( 4piepsilon_(0)r) 9 xx 10^&(9) xx( 2 xx 3.8 xx 10^(-7))/ (2.2) xx(2)/( 3.6 xx 10^(-3)) = 8.6 xx 10^(5) N //C`