Centrifugal ForceCentrifugal Force
The inertial force (Fin) comes from the inertial system. Inertial system
is a system that performs a rotation movement with constant angular
speed and constant acceleration. The inertial force (Fin) exhibits adverse
direction from the rotation system, if it goes from the center of rotation to a
circular path. The observer can feel this force only if he/she is standing in the
rotation system. This force is called the centrifugal force (Fin = Fcf).
From the formula we can see that the strength of the centrifugal force
comes from the mass of the body m, the distance between the body from the
center of the circular movement R and the period T that comes from the
center of the circular movement R and the period T that comes from the
angular speed w.
For a better understanding of centrifugal force we will make a conduct a simple
experiment:
National standards (9-12) addressed
National standards (5-8)
addressed
Step 1.
That way you will get the power wire that will be mentioned later.
Step 2.
Step 3.
Step 4.
Step 5.
Step 6.
Step 7.
Step 8
Author: Vladimir Simonovski
This site was hosted by the NASA Ames Research Center from 1994-2018 and is now hosted by:Fcf = mv2/R = 4p2mR/T2 = mv2R
Materials:
Instructional goal:
To demonstrate centrifugal force.
Make a hole in the exact center of the bottom of one bottle. Ease off the bottle-top. If there is a stopper, cut it off. Select a rubber band that
is about two-thirds as long as the bottle. Use the matchstick to push the
rubber band through the bottle, loop its end around the matchstick. Tape the
matchstick to the bottom of the bottle. Cut a piece of wire about
one-and-a-half times the length of the bottle, and bend one end of it into
a hook. Pass the hook through the bottles neck and catch the bands loose
end.
Picture 1.
Cut an arm out of thick cardboard to the size shown previous. Punch a
hole in its exact center. Glue two balsa wood blocks to the two ends of the
cardboard arm. Make a small hole through the center of each block.
Unbend the power wire, and poke it through the arm. Bend it down and
tape it firmly to the arm. Wind the arm up a few turns to test that it
rotates freely.
Cut the bottoms off two empty plastic bottles � transparent ones if
possible.
Punch two small holes in them. Cut two lengths of wire, about
one-and-a-half times the width of the tubs.
To fasten the tubs to the balsa wood blocks, thread the wires through the
holes.
Then twist the ends over the rims of the tubs. Check that the tubs can
swing freely.
Testing time! Wind the arm up. Then press a finger over its center to
serve as a brake. Keeping a firm hold on the base, ease your finger off. The arm
should gain speed gently. Wind up about 50 turns.
Cut a slider out of postcard to fit the dimensions of the arm. Bend the
edges over. Wind the arm up, and put the slider on its exact center. Let
the arm spin. The slider will stay in place. But if you put the slider just a
little off center it will move away from the center hole. This outward momentum
is called centrifugal force.
Try the same trick, but this time with water. Fill the two tubs about half
full. Make sure there are no leaks. Take care that the arm speeds up at
a steady rate. See what will happen with the water.
Curator: Al Globus
If you find any errors on this page contact Al Globus.
