Hour hand of a clock is 6,cm long. magnitude of displacement of tip of hour between 1:00,PM to 5:00,

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3-2.Motion in Plane

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The hour hand of a clock is $6\,cm$ long. The magnitude of the displacement of the tip of hour between $1:00\,PM$ to $5:00\,PM$ is

A$6\,cm$

B$6\sqrt 3\,cm$

C$12\,cm$

D$3\sqrt 3\,cm$

Solution

$R = 2a\,cos\,\theta /2 = 2 \times 6 \times cos\,30^o = 6\sqrt 3$

Standard 11

Physics

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