SCIENCE CONCEPT:
- Thermals are the warm air currents that rise from the ground that the birds use
to glide upon.
STUDENT OBJECTIVE:
- The student will observe the motions of the fan due to currents of warm air
called thermals.
OVERVIEW:
- The student will make a paper fan and hang it over a heat source to observe the
twirling motion of the fan due to the effects of heat (thermals).
TEACHER TEXT:
-
Although true flyers, some birds also glide and soar. Perhaps to rest their
wings, hawks, vultures, and gulls sometimes glide. As they glide, they drop
lower and lower until finally they must start flapping again to
stay up in the air. At other times, they have been known to soar
higher and higher for hours on warm air currents called thermals.
True flight was achieved between 250,000,000 to 65,000,000 years ago by the
pterosaurs (Greek for feather winged lizard). Although most scientists feel the
larger pterosaurs may have used thermals to soar and glide, these giant reptiles
are believed to be the first non-insect to develop flapping, sustained flight.
While the most well-known of these flying dinosaurs is the Pterodactyl, the
largest of the pterosaurs was the North American Quetzalcatlus with a wingspan
of 40 feet from tip to tip. That is as wide as some planes are today.
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PREPARATION TIME:
- 30 minutes.
LESSON TIME:
- 30 minutes.
TEACHER PREP:
- Photocopy the pattern onto assorted multicolored paper and assemble materials.
Cut different lengths of thread.
WORDS TO KNOW:
- air
- weather
- warmer
- lighter
- upward
- thermals
- current
- cool
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