The length of the minute hand of a clock is 5 cm. Find the area swept by the minute hand during the time period 6: 05 am and 6: 40 am.
Length of the minute hand = 5 cm = Radius of the clock
Minutes between the time period 6:05 am to 6:40 am = 35 minutes
In 60 minutes, the minute hand completes one revolution, i.e. 360°.
∴ Angle made by minute hand in 1 minute = 360°/60° = 60°
Thus angle made by minute hand in 35 minutes = 60° × 35 = 210°
Angle made by minute hand in 35 minutes (in radians) = θ = (210π/180)
∴ Area swept by minute hand in 35 minutes = 
= 275/6
= 45.833 cm2
Hence, the required area swept by the minute land is 45.833 cm2
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