Inquiry 16.0 Introduction to Tides
Introduction:
Have you ever built a sandcastle on an
ocean beach only to find it washed
away a few hours later? Every 6 to 12
hours or so in most places along the
shore, the water rises and falls in a
regular cycle called “tides.” What
causes this phenomenon? In this
inquiry you will apply what you know
about the Sun-Earth-Moon system to
the
occurrence of tides on Earth. To begin,
you
will read about the effect of tides on
organisms along the shore. You will brainstorm what you know about ocean tides. After
viewing a video model of tides, you will consider how the relative position of the Sun,
Earth, and Moon causes ocean tides on Earth. How do the times of high and low tides
along the Atlantic Ocean change each day and throughout the month? Is the there any
relationship between moonrise and moonset times and tides? Does the phase of the Moon
affect tides?
Procedures: write the answer to the questions below in your science spiral.
Read “Marching to the Beat of Tides,” from the teachers website.
A. Discuss with your group the following question:
1) Give one example of an organism that is affected by tidal rhythms.
2) Why does the story say that tides are like clocks?
3) How do you think Fiddler crabs that are taken from their natural home (the ocean)
are active during low tides when they are not at sea?
4) Make a list of what you already know about ocean tides.
B. Get your teachers attention to show your completion of the steps above.
C. Go to your lab station and get your box of materials.
D. Pick up the water balloon and have the balloon rest in the palm of your hand.
E. Shine the flash light on the balloon so it casts a shadow on the white board.
F. Trace the shadow made by the balloon on the white board.
G. Hold the balloon by the mouth piece (neck) of the balloon.
H. Shine the flash light on the balloon so it casts a shadow on the 2nd white board.
I) Trace the shadow made by the balloon on the 2nd white board.
5) How did the balloon’s shape change under the influence of the “pull” of your hand
and influence of Earth’s gravity?
6) How do you think this balloon (in this inquiry) is similar to the Earth?
7) What do you think would cause the Earth to elongate (stretch out)?