Hooked on Science: Newton's Thanksgiving tablecloth trick

Materials

• Several heavy dishes
• Tablecloth without a hem
• Square table with an edge

Instructions

• STEP 1: Place the tablecloth on the table and then arrange the dishes on the tablecloth. Grab the edges of the tablecloth, quickly pull down toward the floor and observe. Record your observations.
• STEP 2: Place the tablecloth on the table again and arrange the dishes exactly the same way you did before on the tablecloth. Grab the edges of the tablecloth, pull down toward the floor faster than what you did the first time, and observe. Record your observations.
• STEP 3: Compare the effects of the different strengths of pulls on the motion of the tablecloth. What happens to the dishes each time? Describe and provide evidence of the effects of balanced and unbalanced forces on the motion of the dishes.

Explanation

The dishes stay on the table as you quickly remove the tablecloth. This happens because of inertia. Inertia is the tendency of an object to resist change. The dishes resist the change taking place underneath them and remain in place. The heavier an object is, the more inertia it has. This is why plastic or paper dishes will not work for this experiment. They do not have enough inertia and will not resist the change taking place underneath them.