A rotating water sprinkler makes one revolution every 15 seconds. The water reaches a distance of 5 metres from the sprinklers.

Question

what is the arc length of the sector watered when the sprinkler rotates through 5pi/3?

Answer 1

C = 2πr           formula

C = 2π5          substitute

C = 10π

 

Arc = [(5π/3) / 2π] [10π]

Arc = (5/6)(10π)

Arc = 50π/6

Arc = 25π/3