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Maeola Walker Chicago Board of Education
1819 W. Pershing Rd.
Chicago IL 60609
This lesson is for primary students. The main objective of this mini-teach is
for students to learn and understand what inertia is. They will learn the
difference between inertia for objects at rest and objects moving in a straight
Two dolls (Barbie & Ken), two carts (skates, skate board)
Place one doll in each cart. Secure one doll with a rubber band, tape or
string. Push the carts into a wall. Ask the students what happened and why.
(Doll not secured should fly out or fall forward). Talk about seat belts.
Two identical coffee cans and a hammer.
Fill one of the cans with a mass (a piece of metal) that will stay in place.
Keep top opening of the cans away from the class when placing them on top of
table or smooth surface floor. Tap one can lightly with the hammer, and ask
students to keep their eyes on the can. Next tap the second can with the
hammer, ask the students to watch that can and ask them which can rolled the
farthest ... why? (The can with the mass will not go as far as the empty can
because the full can has a lot of inertia and tends to stay at rest).
A 2 X 4 block of wood, a dowel & a hammer
Drill a hole the diameter of the dowel through the block of wood. Insert the
dowel loosely into the block and hold the block precariously suspended. Hit the
top of the dowel with the hammer. You will drive the dowel through the block,
but the block of wood will not move since its inertia will try to keep it in
place, even though that place happens to be in mid air.
Large size textbook & friction beads
Place a book on top of a large size desk top. Give the book a thrust with one
hand and see how far the book will slide across the desk top. Next sprinkle
beads on desk top then place the book on the top of the beads, now see how far
the book will slide across the desk top. The book has inertia in each case and
tend to keep moving. The reason the book stops in one case is friction.
A three foot length of dowel & a 2 X 5 board
Drill a hole the diameter of the dowel in the board. Cone shape one end of the
dowel. Place the dowel on the floor with the flat end of the stick (dowel) on
the floor. Next place the board on the cone end of the stick until at rest.
Raise the stick into the air and pound stick heavily onto the floor. The board
should slide to bottom of stick until it hits the floor...why? (because of the
inertia in the board.)
Three 3 X 5" boards & a hammer
Stack the boards on top of each other. Hit the bottom board horizontally with
the hammer. Watch the two boards on top drop into place. Repeat the process
with the second board and watch the top board drop into place.
Felt or cloth table cloth
8 Meter sticks
2 Pool Balls
1 Pool cue (wood dowel)
1 One marker & a quarter
Stretch out the table cloth taut and pin it down with the meter sticks and
clamps. Put an eight inch circle in the center and another 14 inch circle
around the eight inch one.
Place the pool ball in the center with a quarter on top of it. Challenge the
students to knock the quarter outside the small circle. Students may not hit
the quarter with the pool ball they are shooting at it, and they may not start
closer than the large circle.
A 5-gallon bottle, crochet hoop & ink pen with a flat top
Place the bottle on a table top. Next balance hoop on bottle top then balance
pen on top of hoop. Snatch the hoop from the inside real fast and watch the pen
drop into the bottle. The only force acting on the pen is gravity which pulls
it straight down.
Students' performance assessment will be measured by their participation and
interest in each activity followed by a test on inertia. The students will
leave the class with a through understanding of Newton's first Law of Motion.