OCE 1001 Chapter 8 (Sections 8.0-8.4) Quiz Questions for Tuesday, September 25:1. What are the primary factors that determine wave height? (Ch. 8, Section “Wave Terminology”)Wind speed, wind duration, fetch (distance over which wind blows)2. If you have two deep-water waves with periods of 5 and 10 seconds, what can you say about their speeds? (Ch. 8, Section 8.3, Figure 8.8) (See figure below) The longer period wave will have greater speed.Deep water wave speed as function of wavelength and period. These waves are dispersive; the long wavelength waves travel faster.3. Where would it be most likely that you would find internal waves in the ocean? (Ch. 8, Section “What Causes Waves?”)Between low and high density water4. What is the difference between longitudinal waves and transverse waves? (Ch. 8, Section “How do waves move?”Longitudinal waves move side to side and transverse waves move up and down5. Describe circular orbital motion. (Ch. 8, Section “What characteristics do waves possess?”)Water particles move in a circle6. How can you calculate wave speed? (Ch. 8, Section “What characteristics do waves possess?”)Wavelength (L) divided by wave period (T)7. What are shallow-water waves? (Ch. 8, Section “What characteristics do waves possess?”)When water depth is less than wavelength (L)/20; wave orbits are squashed into ellipses8. What are transitional waves? (Ch. 8, Section “What characteristics do waves possess?”)They have characteristics of both deep and shallow water waves. Celerity depends on both water depth and wavelength.1/20 wavelength LESS THAN OR EQUAL TO depth LESS THAN OR EQUAL TO ½ wavelength9. Describe how wind-generated waves develop. (Ch. 8, Section “How do wind-generated waves develop?”)Frictional forces between wind and water and transmit energy to waterCapillary waves (ripples with rounded crests small wavelengths)Gravity waves (buildup of ripples, symmetrical waves with longer wavelengths)Trochoidal waveforms (H/L greater than 1/7, crests pointed, troughs rounded)10. What is constructive interference? (Ch. 8, Section “How do wind-generated waves develop?”)In-phase wave trains with about the same wavelengthsIf your submarine wanted to avoid feeling the wave effect of a 200 ft wave you’d have to go down 100 feet. L/2OCE 1001 Chapter 8 (Sections 8.5-8.7) Quiz Questions for Thursday, October 4:1. Why do tsunami waves always behave as shallow water waves? (Ch. 8, Section “Shallow-Water Waves”)Their wavelengths are long enough that anywhere in the ocean the water depth is less than L/20.2. What causes tsunamis? (Ch. 8, Section “How Are Tsunami Created?”)Sudden changes in sea floor caused by earthquakes, submarine landslides, and/or volcanic eruptions3. Why does wave height increase in shallow water? (Ch. 8, Section “How do Waves Change in the Surf Zone?”)Wave orbital motion is constricted by the sea bottom.4. What is wave reflection? (Ch. 8, Section “How Do Waves Change in the Surf Zone?”)Waves and wave energy is bounced back from barrier.-reflected wave can interfere with next incoming waveWave reflection is explained by which of the following?The bouncing back of wave energy caused by waves striking a hard barrier.5. What is wave refraction? (Ch. 8, Section “How Do Waves Change in the Surf Zone?”)As waves approach shore, they bend so wave crests are nearly parallel to shore.-wave speed is proportional to depth of water (shallow water wave)-different segments of wave crest travel at different speeds6. How are standing waves formed? (Ch. 8, Section “How Do Waves Change in the Surf Zone?”)Two waves with the same wavelength move in opposite directions.-water particles move vertically and horizontally-water sloshes back and forth, bath tub, see-saw7. How does the tsunami warning system in the Pacific ocean work? (Ch. 8, Section “How Are Tsunami Created?”)Pacific Tsunami Warning Center (PTWC) – uses seismic wave recordings to forecast tsunamiDeep Ocean Assessment and Reporting of Tsunami (DART) – system of buoys, detects pulse of tsunami passing8. What are the 3 types of breakers and how are they generated? (Ch. 8, Section “How Do Waves Change in the Surf Zone?”)-spilling breaker: gentle sloping sea floor, wave energy expanded over longer distance, water slides down front slope of wave-plunging breakers: moderately steep sea floor, wave energy expended over shorter distance, best for board surfers, curling wave crest-surging breakers: steepest sea floor, energy spread over short distance, best for body surfing, waves break on the shoreOCE 1001 Chapter 9 Quiz Questions for Tuesday, October 9:1. If the moon had an iron core, what would happen to lunar tides?The tides would become larger because the moon is more massive2. The lunar tidal bulge has a period of 12 hours and 25 minutes, but the solar tidal bulge period is 12 hours. Why the difference? (Ch. 9 Section “Earth’s Rotation and Tides”)The moon is moving also along with the Earth in its orbit3. Why are spring tides highest when the Moon is near perigee? (Ch. 9, Section “How Do Tides Vary During a Monthly Tidal Cycle?”)The moon is very close to Earth, so gravitational force is greater (apogee when moon is far away)Moon, sun, and Earth are aligned, moon and sun bulges are aligned (full moon)Perihelion (January) – Sun is closest to Earth (aphelion when sun is far away)4. If a point on the coast experiences a semi-diurnal tide, what does the daily tide record show? (Ch. 9, Section “What Types of Tidal Patterns Exist?”)Two nearly equal high tides and two nearly equal low tides each dayOne high tide and one low tide per day (polar regions)Semidiurnal – two high tides/two low tides per day, equal strength (equator)Mixed – two high tides/two low tides, most common5. In the absence of friction (and other complicating factors) where would the maximum ideal lunar tide occur? (Ch. 9, Section “Tidal Bulges: the Moon’s Effect”)At two points, directly beneath and opposite the moon.6. Tides would be easy to predict if…?Earth were a uniform sphere covered with an ocean of uniform depth1/r3 = resultant forces (of gravitational and centripetal) proportional toDeclination – angular distance moon and sun, throws off tides from equator by 28.5 degreesLunar tides delayed by 50 minutes everydayOCE 1001 Chapter 9 continued Quiz Questions for Thursday, October 9:1. If you are in a boat in an estuary, when will tidal currents going
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