Ten seconds after an electric fan is turned on, the fan rotates at 300rev/min. Its average angular acceleration is:
Correct answer: C. 3.14 rad/s-2
- A. 30 rad/s2
- B. 30 rev/s2
- C. 3.14 rad/s-2
- D. 500 rev/s2
Explanation
To find the average angular acceleration, we convert the initial and final angular velocities to radians/second, then use the formula α = (Change in angular velocity) / (Change in time). The correct average angular acceleration is 3.14 rad/s-2, calculated from the given initial and final angular velocities and time interval.The other options are incorrect as they do not align with the calculations based on the provided data.ωi = 0 rad s⁻¹ωf = 300 rev / min = 10π rad s⁻¹α = (ωf - ωi) / t = 10π / 10 => α = 3.14 rad s⁻²
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About Acceleration
Acceleration measures the rate at which velocity changes with time, including changes in speed, direction or both. Work includes average and instantaneous acceleration, the relation a = Δv/Δt, uniform acceleration equations, and interpreting velocity time and displacement time graphs, with acceleration carefully distinguished from velocity.
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