The Field Just Outside the Surface of a Long Conducting

Multiple Choice

The field just outside the surface of a long conducting cylinder which has a 2.0-cm radius points radially outward and has a magnitude of 200 N/C. What is the charge density on the surface of the cylinder?

A) 2.7 nC/m²
B) 1.8 nC/m²
C) 3.5 nC/m²
D) 4.4 nC/m²
E) 0.90 nC/m²