# Circular motion helpWatch

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#1
Hello,

I have a question I just cannot get to the bottom of. Can someone please point out what I'm doing incorrectly before I go insane?

Question:
A particle travels at a constant speed around a circle of radius r with centripetal acceleration a. What is the time taken for ten complete rotations.

I tried using the a=w²r equation initially. Replacing w=2π/T

-This gave me a=(2π/10T)²r

-Then I did √(a/r) ×1/2π=10T

-And then √(r/a) ×2π=10T

And I couldn't go any further.
I think I'm either using the 10 rotations incorrectly or I rearranged incorrectly.
0
4 weeks ago
#2
so yeah a=w^2r
a=4pi^2r/T^2
so T^2 = 4pi^2r/a
T= 2pi root r/a
so 10T = 20pi root r/a
1
#3
so yeah a=w^2r
a=4pi^2r/T^2
so T^2 = 4pi^2r/a
T= 2pi root r/a
so 10T = 20pi root r/a
Thank you lol
I should gone with my intuition and actually squared 2π/T!
1
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