Q. Electromagnetic waves travel in a medium which has relative permeability 1.3 and relative permittivity 2.14. Then the speed of the electromagnetic wave in the medium will be
A) $13.6 \times 10^{6}\ m/s$
B) $1.8 \times 10^{2}\ m/s$
C) $3.6 \times 10^{8}\ m/s$
D) $1.8 \times 10^{8}\ m/s$
Explanation
(d) $v = \frac{c}{\sqrt{\mu_{r}\varepsilon_{r}}} = \frac{3 \times 10^{8}}{\sqrt{1.3 \times 2.14}} = 1.8 \times 10^{8}m/s$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.