test-bank-principles-of-computer-networks-and-communications-1st-edition

True-False Questions 1. Electricity consists of a flow of electrons called current, whose magnitude is measured in ampere and strength in volts. Answer: True Difficulty: Easy Page Reference: 26 2. Signals progress along a medium by a process called propagation. Answer: True Difficulty: Easy Page Reference: 26 3. The ampere, a unit of measure of the magnitude of electrical current, is named after Andre Marie Ampere, a French mathematician, chemist, and physicist. Answer: True Difficulty: Medium Page Reference: 28 4. The volt, a unit of measure of electrical potential or pressure, is named after the Italian physicist Alessandro Giuseppe Volta (), who did much pioneering work in electricity. Answer: False Difficulty: Easy Page Reference: 28 5. The ohm, a measure of resistance to current flow, is named after Georg Simon Ohm, a German mathematician who investigated electricity and magnetism. Answer: True Difficulty: Easy Page Reference: 28 6. The type of electricity most relevant to telecommunications is alternating current (AC) – the kind that utility companies provide. Answer:True Difficulty: Easy Page Reference: 28 7. Sine waves are not periodic. Answer:False Difficulty: Medium Page Reference: 30 8. The distance a wave travels in one cycle is its wavelength. Answer:True Difficulty: Medium Page Reference: 31 Chapter 2 THE Modern Signal carriers: Electricity, Light, Media, and Impairments 9. Impulse noise, also called spikes, is unpredictable, usually of very short duration, and composed of large, sudden power surges. Answer:False Difficulty: Medium Page Reference: 32 10. Because delay differences are magnified by distance, delay distortion is another limiting factor of network cable length. Answer: True Difficulty: Medium Page Reference: 32 11. Because thermal noise can be eliminated, it is not a major factor in electrical signal transmission, and does not limit the distance that a signal can travel before it attenuates too much to be distinguished from the noise. Answer: False Difficulty: Medium Page Reference: 32 12. Delay distortion stems from the way wires affect signal velocity. Answer: True Difficulty: Easy Page Reference: 32 13. Thermal noise cannot be eliminated by shielding the cable. Answer: True Difficulty: Medium Page Reference: 32 14. Currently, the most commonly used guided electrical medium in network communications systems is twisted pair. Answer: True Difficulty: Medium Page Reference: 33 15. The lower the cat number, the more capable the wire is of carrying higher-speed data signals reliably and the more it costs. Answer: False Difficulty: Mediu