Circular motion help Watch

ZombieTheWolf
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Report Thread starter 4 weeks ago
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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.

The answer is 20π ×√(r/a)

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.
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homemadeclock
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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
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ZombieTheWolf
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(Original post by homemadeclock)
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!
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