Answer: (1) 1.28 × 105 N/C
- The charge present inside the sphere (q) = 3.2×10-7C
- The electric field is to be determined at a point at r = 15cm
Because the point is outside the sphere, the electric field can be calculated by considering a point charge of the same magnitude 15 cm away from the sphere, because the entire charge is concentrated at the centre.
Substitute the given value
E = 1.28 × 105 N/C