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 × 10−²ms−¹
B. 1.85 × 10−³ms−¹
C. 9.50 × 10−¹ms−¹
D. 5.25 × 10−³ms−¹

 

Correct Answer: Option A

A. 1.05 × 10−²ms−¹

Explanation

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

Thus, ω = θ = 2π/60

Velocity of the tip of the hand, V = ωr

V = 2π/60 × 0.1 = 2π/600 =

π/300 = 3.142/300

V = 0.01047 = 1.05 × 10−²ms−¹