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An electric fan goes from rest to 2100 rpm in 5.0 s. What is the average angular acceleration of the fan during this time?

A. 420 rad/s²

B. 210 rad/s²

C. 105 rad/s²

D. 42 rad/s²

1 Answer

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Final answer:

The average angular acceleration of the fan during this time is approximately 73.3 rad/s².

Step-by-step explanation:

To find the average angular acceleration of the fan, we need to use the formula:

Angular acceleration (α) = (final angular velocity - initial angular velocity) / time

Given that the fan goes from rest (0 rpm) to 2100 rpm in 5.0 s, the initial angular velocity is 0 rpm and the final angular velocity is 2100 rpm. Converting the angular velocities to rad/s, we have 0 rad/s and 220 π rad/min respectively. This gives us:

Angular acceleration (α) = (220 π rad/min - 0 rad/s) / 5.0 s

Converting minutes to seconds, we find:

Angular acceleration (α) = 220 π rad/min = (220 π rad/min)/(60 s/min) = 220 π / 60 rad/s

So the average angular acceleration of the fan during this time is approximately:

α = 220 π / 60 rad/s = 73.3 rad/s²

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