Expansion and Contraction of Rings using Ball

A dewar of liquid nitrogen, a metal ball suspended from a stand rod, a meeker burner, and 2 metal rings rest on a bench

Concept Overview:

1. Expansion of a warm metal

2. Contraction of a cool metal

Lecturer Procedure

Step(s) to Follow	Expected Result
1. Using the ring labeled "hot", attempt to put ball through ring. 2. Hold ring in Meeker burner flame for 20-30 seconds. 3. Attempt to put ball through ring again.	Although the ball would not originally fit through the ring, once heated, the ball will easily fit
1. Using the ring labeled "cold", put ball through ring to show that it will fit. 2. Hold ring in liquid nitrogen for 5-10 seconds. 3. Attempt to put ball through ring	Although the ball easily fit through the ring initially, now that the ring has cooled, the ball will not fit.

Step(s) to Follow

Expected Result

1. Using the ring labeled "hot", attempt to put ball through ring.

2. Hold ring in Meeker burner flame for 20-30 seconds.

3. Attempt to put ball through ring again.

Although the ball would not originally fit through the ring, once heated, the ball will easily fit

1. Using the ring labeled "cold", put ball through ring to show that it will fit.

2. Hold ring in liquid nitrogen for 5-10 seconds.

3. Attempt to put ball through ring

Although the ball easily fit through the ring initially, now that the ring has cooled, the ball will not fit.