In an electromagnetic wave in free space, the electric and magnetic fields are A. parallel to one another and perpendicular to the direction of wave propagation. B. parallel to one another and parallel to the direction of wave propagation. C. perpendicular to one another and perpendicular to the direction of wave propagation. D. perpendicular to one another and parallel to the direction of wave propagation.

C. perpendicular to one another and perpendicular to the direction of wave propagation.

Explanation:

An Electromagnetic wave (EM wave) is a wave having both electric and magnetic components in it. These wave radiates electromagnetic energy while propagating through the space. The electric and magnetic field component of the wave have an angle of 90° to each other aming them perpendicular while they both are perpendicular to the direction of wave propagation as well.

Some examples of EM waves are: UV rays, IR radiation, Radio waves etc. These waves propagate at the speed of light in vacuum.

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