Why the semicircle method works
Power Mechanics · Grade 10 · about 40 minutes
The angle in a semicircle, why it puts the contact points where they are, and the proof that the two tangent lengths are equal.
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- 7 sections of explanation, worked examples and diagrams
- 1 practice task with hints and worked answers
- A quiz that marks itself as you go
- Your progress kept across every subject you take
Other lessons in this sub-strand
- What a tangent is
- A tangent at a point on the circle
- A tangent from a point outside the circle
- Why the semicircle method works
- Tangents parallel and square to a line
- External tangents to two equal circles
- External tangents to two unequal circles
- Internal tangents to two equal circles
- Internal tangents to two unequal circles
- Tangent length
- Checking a tangent construction
- Tangency in belt and chain drives
- Tangency in gears, cams and wheels
- Why tangency matters in drawing