What is the speed of electromagnetic waves (in a vacuum) ?

a.

3.0 x 103 m/s

b.

3.0 x 108 m/s

c.

8.0 x 103 m/s

d.

4.8 x 109 km/hr

An electromagnetic wave transports its energy through a vacuum at a speed of 3.00 x 108 m/s (a speed value commonly represented by the symbol c). The propagation of an electromagnetic wave through a material medium occurs at a net speed which is less than 3.00 x 108 m/s.

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