# physics

posted by kayla

A little boy jumps onto a small merry-go-round(radius 2.00m) in a park that rotates for 2.30s through an arc length of 2.55 before coming to rest. If he landed( and stayed at a distance of 1.75 , frp, tje cemtral axis of rotation of the merry-go-round, what was his average angular speed and average tangential speed?

I got one answer and that is v=1.11m/s but I cant get the other answer.

1. Scott

angular ... 2.55 rad / 2.30 s

2. Damon

I think the arc length is the distance along the circumference here.
r theta = 2.55
theta = 2.55/2 = 1.275 radians
so I get
omega = 1.275/2.30 = 0.554 radians/second

he went from 0 to 0.554 rad/s so his average omega is 0.277 rad/s
so v = omega r
= 0.277 * 1.75 = 0.485 meters/s

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