The merry-go-round at the fair rotates 12 times each minute, and children are 15 feet from the center of the wheel when they are in their seats. What is the linear velocity of the children in feet per hour?

Answer: 16.33 feet/s

Explanation:

1) dа ta:

a) circular motion

b) revolutions: 12 rpm

c) r = 15 feet

d) v = ?

2) Formulae:

angular velocity: ω = number of rpm * 2π / 60 seconds

linear velocity: v = ω * r

3) Solution:

ω = 12 * 2π / 60 s = 0.4π rad / s

v = 0.4π rad / s * 13 feet = 5,2 π feet / s ≈ 5,2 (3.14159) feet / s = 16.33 feet/s.

That is the answer.