Objects Race 500
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Eloise Dillon Newton Bateman
4214 N. Richmond
Chicago IL 60618
To determine how shape affects speed.
balls Various solid disks
can of beef broth can of mushroom soup
Three yardsticks Two cans of Comet
Glass jar with lid construction paper
books or blocks A smooth flat board
Clear plastic bottle Blue food coloring
table Four right angle screw clamps
Set of same mass/same size wooden hoop and metal disk (momentum set)
Set of same mass/same size/different distribution sticks (momentum sticks)
a. Set up incline plane.
b. Prior to lesson empty one container of Comet into the glass jar and seal
the empty Comet container with the lid and set it aside out of sight.
Collect twenty objects that roll smoothly from the material listed above.
c. Fill plastic bottle half full with water. Add a few drops of blue food
coloring to the water. Set this aside out of sight.
d. Place pair of right angle screw clamps on opposite ends of one yardstick.
Place pair of right angle screw clamps near the center of one yardstick
allowing enough space to hold the yard stick between the clamps. Place the
momentum sticks and set on the table off to one side.
e. Place scale on the table.
g. Make three signs: OBJECTS RACE 500, WINNERS, and NONWINNERS. Tape the
signs WINNERS and NONWINNERS at bottom of the chalkboard tray at opposite
h. Make an elimination grid by listing the numbers one through sixteen
vertically on the board. Have children write down names of object next to
number on the board. Start the race by calling children up with their
objects. Place the objects at the high end of the incline plane. Align
the objects behind a yardstick. Countdown from three to zero. Lift the
yardstick straight up. Allow the objects to roll down the incline plane.
The first object down the incline plane is the winner of that race. The
nonwinning object is to be placed on the bottom ledge by the NONWINNERS
sign. The winning object races the winner of the next race. Repeat
process until all eight races are completed in the first round. If there
is a tie try switching the position of racing the objects. Race objects
back to back. If one object clearly pulls away from the other that object
will be faster. Ask the children to make observations about the nonwinning
objects and do the same for the winning objects. Repeat the process until
all races are completed. Ask the children to make observations about the
winning objects and the nonwinning objects.
i. Tell the children that you would like to have some fantasy races with more
objects. Proceed with these pairings for the races: the momentum set, the
can of beef broth and mushroom soup, can of beef broth and wooden disk and
the last race will be the empty can of Comet and the full can of Comet.
j. Ask the children to predict which object do they think will win in each
of fantasy races.
k. The results will be that the wooden disk will be faster than the metal
hoop. The can of beef broth will be faster than the can of mushroom soup.
The empty can of Comet will be faster than the full can of Comet. The full
can of Comet will roll a little distance and then come to a full stop. The
beef broth will beat the metal hoop because the liquid inside is sliding
down the incline. Illustrate this by rolling the bottle of blue water down
l. Use the momentum sticks. Swing the sticks out away from your body. It
will be easier to swing the momentum stick that has its mass closer towards
the center than the one that has the mass distributed towards the end.
This can be illustrated by repeating the swings with the yardsticks. The
yardstick with the right angle clamps near the end illustrates the metal
hoop and the empty can of Comet. The yardstick with the right angle clamps
near the middle illustrates solids such as the wooden disks, balls, and the
can of mushroom soup.
m. Look again at the race between the momentum set(wooden disk and metal
hoop). Show with the scale that both objects have the same mass. Remind
them that the disk was faster than the hoop. Ask the children to make
observations. Is weight a factor? No it is not. The faster objects have
a center of gravity closer towards the middle similar to the yardstick
with the right angle clamp near the middle. The hoops have their center of
gravity distributed closer to the rim illustrated by the other yardstick
with the clamps attached at the end.
n. The full can of Comet was the slowest because the powder inside was also
turning trying to reach its own center of gravity while the can was
rolling down incline. Illustrate this by rolling the glass bottle of Comet
down the incline.
Rank these objects in the order that they would finish in a fantasy race
and tell why each object finished in that order. Use a disk, a can of
soda, a hoop and a ball.
Two hundred and one awesome, magical, bizarre, and incredible
experiments by Janice VanCleave.