Investigation 82 Tides and the Moon Update TOC with date, Inv. #, Title, and page # Notes section: date, Inv. #, Title, and page # Focus Question: What is the relationship between the phase of the Moon and extreme tides? Answer Focus Question Draw 1st Line of Learning

Vocabulary tide-the alternate rising and falling of the sea, usually twice in each lunar day at a particular place, due to the attraction of the moon and sun high tide-the state of the tide when at its highest level low tide-the state of the tide when at its lowest level extreme tide-when there is the greatest daily variation between the heights of the low and high tides

Key Concepts and Process Skills 1. Extreme tides occur on or near the full Moon and new Moon. 2. Often there is a scientific explanation for a correlation between physical events. 3. Gravity and the rotation of Earth explain the tides.

Reasons for the extreme tides

1a. Count the number of days between the full moons, and list them. Hint: you should list 4 numbers. There are 29, 29, 30, and 30 days between the full moons.

b. Calculate the average number of days between full moons. The average moon cycle is close to 29.5 days.

c. Use your average to predict the date of the next full Moon after the one on September 13. Adding 29 or 30 days to September 13 gives October 12 or 13.

2. Based on the data on your Student Sheet, how often do sets of extreme tides (both high and low) occur? Extreme tides occur about twice every 29 or 30 days, or about twice a month.

3. What is the connection between extreme tides and the phase of the Moon? Use evidence from your calendar to support your answer. From May to September, there are extreme tides near the full Moon every month. There are also extreme tides about halfway between each full Moon. New Moons occur half way between full moons, which suggests the new Moon is also related to extreme tides. Extreme tides happen twice a month, once near a full Moon and once near a new Moon.