The magnitude of the electric field strength = 7.2 x 10⁸ N/C
Explanation:The linear density:
[tex]\begin{gathered} \lambda=18\mu C\text{ /cm} \\ \\ \lambda=\frac{18*10^{-6}C}{0.01m} \\ \\ \lambda=0.0018\text{ C/m} \end{gathered}[/tex]Point r = 3 cm = 3/100 m
r = 0.03 m
The electric field strength is calculated below
[tex]\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}[/tex]The magnitude of the electric field strength = 7.2 x 10⁸ N/C
