The needle of the speed-indicator flicked and wagged to and fro; the cinders rattled on the roof, and a whirl of dust sucked after the whirling wheels, The crew of the combination sat on their bunks, panting in their shirt- sleeves, and Cheyne found himself among them shouting old, old stories of the railroad that every trainman knows, above the ...
One of the main drawbacks to a digital TV signal or digital cable signal, for instance, is that it is an artificial reproduction of the original data, whereas an analog signal starts out as an exact copy of the original.
Transverse and compressional (longitudinal) waves are similar because have a frequency (and therefore a period), and a wavelength. that can be calculated. Waves come in either two major categories: electromagnetic or mechanical. Electromagnetic waves are light waves. They are energized particles that travel very quickly. They do not need a medium to travel, which means that they can travel through outer space where there is no matter. Mechanical waves are waves that require a medium (matter) to travel. These waves are considered to have two major shapes: transverse and compressional. For waves we can peform calculations using two equations: Frequency is the inverse of the time it takes for one cycle of the wave to occur.