you are sitting on a ferris wheel car. The wheel has a radius of 50 feet and makes 3 revolutions per minute. What is your linear speed in feet per minute?
3 answers
(2π*50ft/rev)(3rev/min) = 300π ft/min
Hi Jenna. You probably know that the formula for the distance around a circle (called the "circumference") having a radius "R" is 2*(PI)*(R).
PI is about 3.14159, rounded down. (And sometimes people just use 3.14 for easier calculation).
So, for a circle where R = 50 feet, then the wheel's circumference = 2*(3.14159)*(50) = 314.16 feet around the circle of the ferris wheel.
So, that's how long it is around the wheel one time. You problem says it goes around 3 times per minute, so just multiply by 3 and you will get that the distance traveled in 3 revolutions (one minute) is 942.48 feet. So the speed per minute is 942.48 feet per minute.
I'm not sure how you're supposed to round this or what value your teacher wants the class to be using for PI. Note if you only use "3.14" for PI, then it comes out exactly at 942 feet per minute.
PI is about 3.14159, rounded down. (And sometimes people just use 3.14 for easier calculation).
So, for a circle where R = 50 feet, then the wheel's circumference = 2*(3.14159)*(50) = 314.16 feet around the circle of the ferris wheel.
So, that's how long it is around the wheel one time. You problem says it goes around 3 times per minute, so just multiply by 3 and you will get that the distance traveled in 3 revolutions (one minute) is 942.48 feet. So the speed per minute is 942.48 feet per minute.
I'm not sure how you're supposed to round this or what value your teacher wants the class to be using for PI. Note if you only use "3.14" for PI, then it comes out exactly at 942 feet per minute.
(P.S. I hadn't seen Steve's answer before the time I got done wandering through mine)
3 answers