The length of the second hand of a watch is 1 cm. The velocity vector of the tip of the second hand in cm per second is
Correct answer: B. 2π/60
- A. 2π
- B. 2π/60
- C. 2π/12×60
- D. 2π/24×60
Explanation
The linear velocity of the tip of the second hand is calculated using the formula: Linear Velocity (v) = Radius (r) * Angular Velocity (ω). By converting the angular velocity from RPM to radians per second, the correct option calculates the linear velocity as 2π/60 cm/s. The other options either neglect the length of the second hand, use incorrect factors in the calculation, or fail to consider the time taken to complete a rotation.v = rωω = (2π / 60) rad s⁻¹v = 1 cm × (2π / 60) = (2π / 60) cm s⁻¹
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