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Question
The minute hand of clock is10cm long. Find the area of the face of the clock described by the minute hand between 8am and 8:25 am
Solution
Radius of minute hand (r) = 10 cm
For 1 hr = 60 min, minute hand completes one revolution = 360°
60 min = 360°
1 min = 6°
From 8 am to 8:25 am it is 25 min angle subtended = 6° × 25 = 150° = 𝜃
Area described =`theta/360^@× pir^2`
=`150/360×22/7`× 10 × 10
=`(250×11)/3`
=`2750/3 cm^2`
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