Question

The electric field strength in an electro-magnetic wave is ${10}^4$ V/m. Then the corresponding magnitude of magnetic field strength (in tesla) in the wave will be:

• A. ${10}^4$
• B. $3\times {10}^{12}$
• C. $3.3\times {10}^{-4}$
• D. $3.3\times {10}^{-5}$

Answer 1

The correct option is D $3.3\times {10}^{-5}$

Given,

$E={10}^{4}V/m$

$c=3\times {10}^{8}m/s$

Magnetic field, $B=\frac{E}{c}$

$B=\frac{{10}^4}{3\times {10}^8}=3.3\times {10}^{-5}T$

The correct option is D.