Wagon wheels

This task is about changes to metal when it is heated or cooled.

Question 1Change answer

wooden wagon wheel with iron rim
Years ago, wooden wheels had iron rims fitted. To fit the iron rim, it was heated, then put around the wooden wheel and allowed to cool.
 
a) What two main changes happen to the iron as it is heated?
1. 2.
 

Question 1Change answer

Once the iron rim is on the wooden wheel it cools.
 
b)  What two main changes happen to the iron as it cools?
1. 2.