Final answer:
Electromagnetic waves and mechanical waves differ in propagation speed, medium requirement, and wavelength characteristics; electromagnetic do not require a medium and travel at the speed of light, whereas mechanical waves require a medium and have a variable speed.
Step-by-step explanation:
When comparing and contrasting electromagnetic waves with mechanical waves, there are several key differences to consider:
- A. Speed of propagation: Electromagnetic waves travel at the speed of light in a vacuum, which is a constant speed of approximately 3 x 108 meters per second. Mechanical waves' speed is dependent on the medium through which they travel and is generally slower than the speed of light.
- B. Need for a medium: Electromagnetic waves do not require a medium and can propagate through a vacuum, while mechanical waves need a medium like solids, liquids, or gases to travel.
- C. Wavelength: Both electromagnetic and mechanical waves have wavelengths, which is the distance between successive crests or troughs. However, electromagnetic waves can have a wide range of wavelengths, from very short (gamma rays) to very long (radio waves), covering the electromagnetic spectrum. Mechanical waves also vary in wavelength, but within the constraints of their medium.
Additionally, while both types of waves have frequency and wavelength characteristics, electromagnetic waves are transverse waves, where the oscillations are perpendicular to the direction of wave propagation, and most mechanical waves (such as sound waves) are longitudinal, where the oscillations are parallel to the wave direction.