Question

What is the electric field at a distance of 10 cm from an isolated point charge of

2 x 10 -9 C?

With solution please?

Answer 1

The electric field due to the point charge

$$E=k\frac{q}{r^2}$$

So

$$E=9*10^9*\frac{2*10^{-9}}{0.1^2}=1800\:\rm N/C$$