Question

Calculate the magnitude of electric field strength at a point 3cm from an infinite line of charge of linear density 18 μC/cm situated in a medium of whose Ԑr = 1.5

Answer 1

Answer:

The magnitude of the electric field strength = 7.2 x 10⁸ N/C

Explanation:

The linear density:

$\begin{gathered} \lambda=18\mu C\text{ /cm} \\ \\ \lambda=\frac{18*10^{-6}C}{0.01m} \\ \\ \lambda=0.0018\text{ C/m} \end{gathered}$

Point r = 3 cm = 3/100 m

r = 0.03 m

The electric field strength is calculated below

$\begin{gathered} E=\frac{\lambda}{2\pi\epsilon_o\epsilon_rr} \\ \\ E=\frac{0.0018}{2\times3.14\times8.85\times10^{-12}\times1.5\times0.03} \\ \\ E=719709237.468\text{ N/C} \\ \\ E=7.2\times10^8\text{ N/C} \\ \end{gathered}$

The magnitude of the electric field strength = 7.2 x 10⁸ N/C