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

[Bogus_Roads]

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?

 

[ehild]

mHz is 0.001 Hz.

ehild

 

[Bogus_Roads]

So B