These three tasks link together to extend and develop the relationship between diameter and circumference.
Longest path
Which is the longest path?
What happens if the length of AB is not known?
What happens if you choose a path that mixes different sized semicircles?
What happens as you increase the number of semicircles?
Round about and back again
An international project has been planned to build a ‘universal watch’ station on the moon. This involves building a fence-like structure around the moon’s equator. The fence will be 3m high and has special wires, 0.5, 1, 1.5, 2, 2.5 and 3m above the ground.
The moon has a diameter of 3476km and it is not unreasonable to assume that it is a perfect sphere.
- How long will each of the six wires be?
- What do you notice?
- How would your answers compare if the structure was higher or the diameter different?
Produce a poster which explains your findings and convinces others of any generalisations you can make.
Staggering – a group working task
Use the link to download group cards which support this task.
The two questions below appeared on a sports site forum and they were not very well answered. Try to help by producing answers that can be understood by the inquirers. Your responses might include information about:
• how distances are calculated
• how things might vary from track to track
• what might happen for different races
• any diagrams you feel will help with your explanations
The two questions
