Question #89041
1 Answer
They are at a higher frequency (shorter wavelengths) than sound waves, propagate at a higher velocity, and are electromagnetic instead of pressure waves.
Explanation:
Our bodies sense organs (eyes, ears) selectively receive them into our brains, producing sight and sound. Mechanical sensors and transducers can be made to detect and generate the full range of frequencies in either light or sound.
There are two main differences between sound waves and light waves. The first difference is in velocity. Sound waves travel through air at the speed of approximately 1,100 feet per second; light waves travel through air and empty space at a speed of approximately 186,000 miles per second. The second difference is that sound is composed of longitudinal waves (alternate compressions and expansions of matter) and light is composed of transverse waves in an electromagnetic field.
Although both are forms of wave motion, sound requires a solid, liquid, or gaseous medium; whereas light travels through empty space. The denser the medium, the greater the speed of sound. The opposite is true of light. Light travels approximately one-third slower in water than in air. Sound travels through all substances, but light cannot pass through opaque materials. From: http://electriciantraining.tpub.com/14182/css/Comparison-Of-Light-Waves-With-Sound-Waves-44.htm
see also:
http://www.pion.cz/en/article/electromagnetic-spectrum