A crawling tractor sprinkler is
located as pictured below, 100 feet South of a
sidewalk. Once the water is turned on, the
sprinkler waters a circular disc of radius 20
feet and moves North along the hose at the rate
of 1/2 inch/second. The hose is perpendicular
to the 10 ft. wide sidewalk. Assume there is
grass on both sides of the sidewalk.

) Find the area of GRASS watered after
one hour

If anybody needs a diagram, it's question 3.6 in Chapter 3 exercises
http://www.math.washington.edu/~m120/TheBook/TB2010-11.pdf

Question

A crawling tractor sprinkler is 
located as pictured below, 100 feet South of a 
sidewalk. Once the water is turned on, the 
sprinkler waters a circular disc of radius 20 
feet and moves North along the hose at the rate 
of 1/2 inch/second. The hose is perpendicular 
to the 10 ft. wide sidewalk. Assume there is 
grass on both sides of the sidewalk. 


) Find the area of GRASS watered after 
one hour 

If anybody needs a diagram, it's question 3.6 in Chapter 3 exercises 
http://www.math.washington.edu/~m120/TheBook/TB2010-11.pdf

dumbcow · Answer

diagram of sprinkler at start and after an hour
|dw:1381486663960:dw|
Area of grass is area of rectangle and 2 half circles at either end minus area of sidewalk
$$A = (150*40)+2(\frac{1}{2}\pi 20^{2}) - (10*40)$$
hope that helps