5.3: Properties of Electromagnetic Waves

• Maxwell


  Using some of the known equations in electromagnetism at that time, he calculated the speed of electromagnetic waves to be 3.0 × 10^8 m/s in an empty space and is denoted as the constant, c
• Electromagnetic waves


  travel slower in denser materials or materials with molecules closer to one another
• Light


  is faster in air than in water, and faster in water than in glass. It travels fastest in vacuum where not even a single molecule can be found.
• Electromagnetic waves are transverse waves made of perpendicular electrical and magnetic field components
• Electromagnetic waves have wavelength, period, and frequency
• The wavelength (λ) refers to the distance the wave covers per cycle of propagation
• wavelength (λ)


  It can be visualized as one “complete” wave in a series of identical waves.
• A wave’s period (T) refers to the time it takes for the wave to finish one complete wavelength to pass through a point.
• the frequency (f) of a wave is the number of complete waves passing through a point in a unit of time
• Frequency and period are reciprocal quantities.
• Speed is distance divided by time.
• For light traveling in a vacuum or empty space, you can readily obtain the period or frequency from a given wavelength and vice versa since speed is a constant quantity.
• The more energy involved in the electromagnetic processes, the faster the production of electromagnetic waves, thus, increasing the wave frequency.