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The length of the seconds hand of laboratory clock is 0.1...

The length of the seconds hand of laboratory clock is 0.1m. Calculate the speed at the top of the seconds hand

A.

1.05 × 10\(^{-2}\)ms\(^{-1}\)

B.

1.85 × 10\(^{-4}\)ms\(^{-1}\)

C.

9.50 × 10\(^{-1}\)ms\(^{-1}\)

D.

5.25 × 10\(^{-3}\)ms\(^{-1}\)

Correct answer is A

Length of the seconds hand = r = 0.1m but the seconds hand rotates through 360° or 2π rad in 60s.

Thus, ω = θ =
60


Velocity of the tip of the hand, V = ωr

V =
60
× 0.1 =
600
= π
300
= 3.142
300


V = 0.01047 = 1.05 × 10\(^{-2}\)ms\(^{-1}\)