| A | B |
|---|
| breaker or surf | a wave that topples over as it approaches shallow water |
| buoyancy | the ability to float |
| crest | the peak, or highest point, of a wave |
| density | the amount of matter in a given volume. The more matter per unit of volume, the denser the substance |
| gravity | the attractive force that exists between all objects |
| high tide | the time at which the tide reaches its highest level. High tide occurs at approximately twelve-hour intervals at any given coastal location |
| low tide | the time at which the tide reaches its lowest level. Low tide occurs approximately six hours after high tide |
| sea | a region of ocean water partly enclosed by land |
| tides | the alternating rise and fall of the surface level of the ocean, caused primarily by the gravitational pull of the moon on Earth |
| trough | the valley, or lowest point, between the crests of two successive waves |
| wave height | the vertical distance between a wave crest and the subsequent trough |
| wavelength | the horizontal distance between two successive wave crests |
| world ocean | the continuous body of salt water that encircles the Earth. The four main oceans plus all the seas make up the world ocean |
| Longshore drift | process of moving sand along the shore when waves hit the beach at an angle |
| frequency | number of waves that pass a specific point in a given period of time |
| tidal energy | energy harnessed from the tides |
| amplitude | maximum distance from rest |
| neap tide | moon and sun at right angles |
| 1st and 3rd quarter | half moon neap tide |
| spring tide | moon, earth, and sun in alignment |
| new and full moon | horizontal line spring tide |
| sandbar | long ridge formed of deposited sand in shallow water |
| rip current | strong current which flows through a narrow opening |
| electricity | energy from the tides can generate |
| clean and renewable | advantage of tidal energy |
| erosion | moving sand from one place to another |
| friction | force which slows down a wave as it reaches the shore |
| moon | object most responsible for tides |
| wind | horizontal movement of air which determines a wave's speed and size |
| two | number of high tides or low tides per day |
| greatest difference | spring tide causes this between high and low tides |
| least difference | neap tide causes this between high and low tides |
| waveheight and frequency | as a wave nears the shore the wavelength decreases, but these increase |
