Centripetal acceleration formula

1. Jan 9, 2016

BensonCa

1. The problem statement, all variables and given/known data
In a certain carnival ride, visitors enter a circular room with radius r=9.1m. The room then begins spinning around its center, reaching an angular speed of 1.7rad/s. What centripetal acceleration do the riders experience?

2. Relevant equations
ac= v^2/r

3. The attempt at a solution
I believed that ac= v^2/r which would equal .3175824176 or .32 m/s^2

but the answer is 26 m/s^2 and the explanation is Centripetal acceleration is given by ac=rω2. WHY?

2. Jan 9, 2016

axmls

You're given angular speed, and you're trying to plug it into a formula with velocity.

3. Jan 9, 2016

rozma3

Good effort though! You have omega, the formula you want to be using is a = w^2 r substituting w = v/r into the original formula you have.

4. Jan 9, 2016

BensonCa

Oh, I see what I did, thank you

5. Jan 17, 2016

Syndickaze

I would rather go with:
v= wr
v =1.7 x 9.1 = 15.47

to find the acceleration:
a = v^2/r
a = (15.47)^2/9.1
a = 231.32/9.1
a = 26.299 ( and can be rounded to 26)