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 à— 10\(^{-2}\)ms\(^{-1}\)
B. 1.85 × 10\(^{-4}\)ms\(^{-1}\)
C. 9.50 à— 10\(^{-1}\)ms\(^{-1}\)
D. 5.25 à— 10\(^{-3}\)ms\(^{-1}\)
Correct Answer:
Explanation
Length of the seconds hand = r = 0.1m but the seconds hand rotates through 360° or 2π rad in 60s.
Thus,
ω
=
θ
=
2Ï€
60
Velocity of the tip of the hand, V = ωr
V
=
2Ï€
60
×
0.1
=
2Ï€
600
=
Ï€
300
=
3.142
300
V = 0.01047 = 1.05 × 10\(^{-2}\)ms\(^{-1}\)
