What is the Correct Frequency of a Child's Swing Motion?

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The discussion centers on calculating the frequency of a child's swing motion, which takes 3 seconds to go from maximum to minimum velocity, indicating it completes half a cycle in that time. To find the frequency, it is established that the full cycle takes 6 seconds, leading to a frequency of 1/6 Hz, or approximately 0.167 Hz. The confusion arises around the unit millihertz (mHz), which is 0.001 Hz. The correct answer is determined to be B, 170 mHz, aligning with the calculated frequency. Understanding the conversion between seconds and hertz is crucial for solving similar problems.
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Homework Statement



In a swing cycle (pendulum), it takes a child 3 seconds to go from maximum velocity to minimum velocity. What is the frequency of the child's motion?

A.80 mHz
B.170 mHz
C.330 mHz
D. 3 Hz

Homework Equations



T=1/f



The Attempt at a Solution



This means it takes 3 second to complete half of the cycle, so 6 seconds to complete the entire cycle, and 1/6 cycles then happen per second. So confused. Millihertz?
 
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mHz is 0.001 Hz.

ehild
 
So B
 
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