A 15 cm long perpendicular is drawn from the centre of a circle to its 40 cm long chord. Find the radius of the circle.
This questions was previously asked in
Combined Graduate level Examination 2023 Tier I
Explanation:
- A perpendicular from the center of a circle to a chord bisects the chord.
- Chord length = 40 cm, so each half is 20 cm.
- A right triangle is formed with the radius as the hypotenuse, half the chord as one leg, and the perpendicular as the other leg.
- Use the Pythagorean theorem: \((\text{radius})^2 = (\text{perpendicular})^2 + (\text{half of chord})^2\).
- Substitute values: \((\text{radius})^2 = 15^2 + 20^2\).
- Calculate: \((\text{radius})^2 = 225 + 400 = 625\).
- Radius = \(\sqrt{625} = 25\) cm.
- Option 1: 25 cm is correct.
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By: Parvesh Mehta ProfileResourcesReport error