Tablecloth Tug

PIRA: 1F20.30

Overview:

With a hard enough tug, inertia can overcome the friction force of an object. We place a few objects onto a tablecloth, and then see how much the friction force acts on the objects. When pulled correctly, we can see that the lighter objects have moved more than the heavy objects.

Materials:

Silk cloth

Plate

Candle holder

Candle

Lighter

Utensils

Wine glass

Setup:

Place the cloth on a table that can be seen by the class. Then place all the other objects on top as if someone is going to dine in that spot. Light the candle and put water (preferably with food coloring) into the wine glass.

How to:

Hold the cloth with both hands at one end of the table. Pull the cloth as quickly as possible. Make sure to pull the cloth straight. If pulled upward, then the objects will fall backwards. If pulled down, there will be more friction on the cloth and will not be pulled out as fast.

Safety:

Do not drink the water, and be careful of the flame on the candle.