Q4 of 36 Page 249

The length of a minute hand of a circular dial is 10 cm. Find the area of the sector formed by the present position and the position after five minute of the minute hand. (π = 3.14)

length of the minute hand (r) = 10 cm


(In clocks the length of minute hand will be radius of that clock dial)


The sector formed by the minute hand after 5 minutes will be as follows.



θ = = 30o


Area of the sector formed by minute hand =


=


= 26.166 cm2


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2

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