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Sweeping Hands


clock

In $10$ minutes, through how many degrees does the minute hand of the clock sweep?

In $3$ hours, how many degrees does the hour hand of the clock sweep through?
If the minute hand goes through $180^{\circ}$, how many degrees does the hour hand sweep?
 

Why do this problem?

This problem is a great context in which to apply knowledge of angles based on a full turn and it helps to consolidate analogue clock features too.

Having a large geared demonstration clock available would be a good idea to discuss this problem with the group.

Key questions

Which is the minute hand and which is the hour hand?
How long does it take the hour hand do go a full circle ($360$ $^\circ$) round the clock?
How long does it take the minute hand do go a full circle round the clock?
How many degrees does the minute hand go through in one hour?
So many degrees does it go through in $15$ minutes? In $10$ minutes?
So, how many degrees does it go through in $5$ minutes?

Possible extension

Learners could go on to either of these two problems - Watch the Clock or Two Clocks .

Possible support

Suggest doing this problem, Two Clocks or possibly just exploring the interactivity to see how clocks move.