Unit 4 Assignment 1
Define Key Terms:
Electrical circuit: A network consisting of a closed loop, giving a return path for the current.
Frequency: The number of occurrences of a repeating event per unit time.
Amplitude: The objective measurement of the degree of change (positive or negative) in atmospheric pressure (the compression and rarefaction of air molecules) caused by sound waves.
Phase: Refers to different places on the sine-wave curve. Normally, the graph of voltage over time changes with a predictable sine wave, as shown at the top part of the right box.
Bit time: The time that passes while the sender encodes 1 bit onto the circuit.
Encoding scheme: The physical layer standard that defines what energy signal means binary 0 and what signal means binary 1.
Unshielded twisted-pair (UTP): Cables have no added shielding materials to prevent EMI problems. The name also refers to the fact that the cable contains twisted pairs, and the twisting does reduce EMI effects between the twisted pair in the same cable (or in nearby cables).
Core: The physical medium that transports optical data signals from an attached light source to a receiving device.
Cladding: Surrounds the core, for the entire length of the cable, and reflects the light into the core. The light waves reflect off the cladding, back into the core, until the light waves reach the other end of the cable.
Radio waves: Work well for networking because as a waveform, radio waves can be changed (modulated) over time to send data. Radio