Question

A plane electromagnetic wave with frequency of 30 MHz travels in free space. At particular point in space and time, electric field is 6 V/m. The magnetic field at this point will be x × 10^-8 T. The value of x is ______.

Options

• 2

• 4

• 6

• 8

Answer 1

A plane electromagnetic wave with frequency of 30 MHz travels in free space. At particular point in space and time, electric field is 6 V/m. The magnetic field at this point will be x × 10^-8 T. The value of x is 2.

Explanation:

Given,

Electric field, E = 6V/m

For an electromagnetic wave, the relationship between the electric field and the magnetic field is given by

|B| = `|"E"|/"c"` 

= `6/3xx10^8`

= 2 × 10^-8 T

∴ x = 2