Name: _________________
Date: ___________
Class Period: ___________
Water On the Move Notes
Define:
Tidal Range:
Tidal Bulge:
Spring Tide:
Neap Tide:
Diagram: Every 28 day (approximately), there are two spring tides and two neap tides. Sketch the
positions of the Earth, Moon, and Sun for each spring and neap tide, and label the areas of high and
low tides, AND the moon phase.
Spring tide
Neap tide
Spring tide
Neap tide
Describe: Why do the gravitational forces of the Sun and Moon on the Earth’s surface differ?
Explain: Why are there two high tides and two low tides every day?
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Name: _________________
Date: ___________
Class Period: ___________
Imagine: What would happen if the Sun’s gravity was not strong enough to affect our tide? Why?
Apply: Label the area of the graph where high tide and low tide are occurring.
Tides for Key West, Fl
0.7
Height of Water in Meters
0.6
0.5
0.4
0.3
0.2
0.1
0
-0.1
-0.2
6/10/2014 0:00
6/11/2014 0:00
6/12/2014 0:00
6/13/2014 0:00
6/14/2014 0:00
Date and Time (M/D/Yr, Hr:Min)
Where would your area be in relation to the Moon during a high tide? A low tide?
Summarize: In 3-5 complete sentences summarize how the Sun and Moon’s gravity affect the Earth’s
tides.
©Copyright 2014-all rights reserved www.cpalms.org
Name: _________________
Date: ___________
Class Period: ___________
Water On the Move Notes- Teacher Guide
Define:
Tidal Range: The difference in height between the high tide and the low tide
Tidal Bulge: The “lump” of water created that occurs on two sides of the Earth, opposite from each
other (where high tides are occurring)
Spring Tide: When the tidal range is the largest during a 28 day period (usually occurs twice)
Neap Tide: When the tidal range is the smallest during a 28 day period (usually occurs twice)
Diagram: Every 28 day (approximately), there are two spring tides and two neap tides. Sketch the
positions of the Earth, Moon, and Sun for each spring and neap tide, and label the areas of high and
low tides, AND the moon phase.
Spring tide
Neap tide
Spring tide
Neap tide
Describe: Why do the gravitational forces of the Sun and Moon on the Earth’s surface differ?
The Sun, although more massive, is much farther from the Earth, meaning that the Sun will have a
much smaller gravitational effect on the Earth’s surface.
Explain: Why are there two high tides and two low tides every day?
The Earth rotates fully approximately every 24 hours, so an area will move through the two tidal bulges
(areas of high tide) and the two areas of lowest tide every day.
©Copyright 2014-all rights reserved www.cpalms.org
Name: _________________
Date: ___________
Class Period: ___________
Imagine: What would happen if the Sun’s gravity was not strong enough to affect our tide? Why?
The Earth would not have spring or neap tides since the gravity of the Sun would not work with or
against that of the Moon’s gravity.
Apply: Label the area of the graph where high tide and low tide are occurring.
0.7
Tides for Key West, Fl
High Tide
High Tide
Height of Water in Meters
0.6
0.5
0.4
High Tide
High Tide
0.3
0.2
0.1
Low Tide
Low Tide
0
-0.1
-0.2
6/10/2014 0:00
Low Tide
6/11/2014 0:00
6/12/2014 0:00
Low6/13/2014
Tide 0:00
6/14/2014 0:00
Date and Time (M/D/Yr, Hr:Min)
Where would your area be in relation to the Moon during a high tide? A low tide?
Summarize: In 3-5 complete sentences summarize how the Sun and Moon’s gravity affect the Earth’s
tides.
Answers will vary, but should include the concept that the Moon’s gravity attracting the Earth’s water
(since it is not attached to the ground) pulls it off the surface in two mounds causing areas of higher
than sea level water (high tides) and areas lower than sea level water (low tides). The Sun’s gravity
also plays a small role when its gravity works with or against the Moon’s gravity, causing spring tides
and neap tides where tidal range is larger than normal or smaller than normal.
©Copyright 2014-all rights reserved www.cpalms.org