What is the speed of the tip of second hand of a clock if its length is 10cm?
Correct answer: A. 1.05cms-1
- A. 1.05cms-1
- B. 2.05cms-1
- C. 1.05m/s
- D. 3.05cms-1
Explanation
Using the formula v=wR, where w is the angular speed (2π/60 rad/s for a second hand), and R is the length of the second hand (10cm), we find v=10×2π/60=3πcm/s≈1.05cm/s. This means that the speed of the tip of the second hand of a clock is approximately 1.05cm/s. The other options are incorrect because they either have the wrong unit (m/s instead of cm/s) or provide slightly different incorrect calculations.
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