1. Chapter 21 Section 3 Handout
Tides

2. 1
The periodic rise and fall of the water level in the ocean is called ________.
tide.

3. 2 The period when the water level is highest is called ___________.
high tide.

4. 3 The period when the water level is lowest is called ___________.
low tide.

5. 4 According to Newton’s law of gravitation, what causes tides?
the gravitational pull of the moon on Earth and Earth’s waters.

6. 5
Why does the ocean on the side of Earth facing the moon bulge slightly?
The gravitational pull of the moon.

7. 6 When tidal bulge occurs, what is caused in the area of the bulge?
High tide.

8. 7 Why does a tidal bulge form on the opposite side of the bulge?
The outward force causes the ocean on the side of Earth opposite the moon to bulge.

9. 8
What causes low tides?
As ocean water flows toward the areas of high tide, the water level in other areas of the ocean drops.

10. 9
How long does it take for all areas of the ocean to pass under the moon?
24 h 50 min

11. Matching Gulf of Mexico coast Pacific Coast
Atlantic Coast of the United States
experiences a mixed tidal pattern featuring a very high tide followed by a very low tide
experiences two high tides and one low tide each day
Experiences one high tide and one low tide each day

12. 19
The slow, rocking motion of ocean water caused by tidal bulges moving around the ocean basins is called ____________.
tidal oscillation.

13. 20 Where is it difficult to see the effects of tidal oscillations?
Along straight coastlines and in the open ocean.

14. 21
Explain why Baltic and Mediterranean Seas have a very small tidal range.
In enclosed seas, tidal oscillations reduce the effects of the tidal bulges.

15. 22 Where might tidal oscillations amplify the effects of tidal bulges?
In small basins and narrow bays located off major ocean basins.

16. The End