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Question
An arc of length 15 cm subtends an angle of 45° at the centre of a circle. Find in terms of ๐, radius of the circle.
Solution
Length of arc = 15cm
๐ = angle subtended at centre = 45°
Let radius = r cm
arc length = `theta/360^@`× 2๐๐
=`45^@/360^@`× 2๐๐
`45/360`× 2๐๐ = 15
๐ =`(15×360)/(45×2pi)=60/pi`cms
๐ ๐๐๐๐ข๐ =`60/pi`cms
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