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Question
The minute hand of a clock is 12 cm long. Find the area swept by in it 35 minutes.
Solution
Angle described by the minute hand in 60 minutes = 360°
Angle described by the minute hand in 35 minutes `=(360/60xx35)^circ`
= 210°
Now,
r = 12 cm and θ = 210°
∴ Required area swept by the minute hand in 35 minutes = Area of the sector with r = 12 cm and θ = 210°
`=(pi"r"^2theta)/360`
`=(22/7xx12xx12xx210/360)"cm"^2`
= 264 cm2
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