# How do i find the tension of an object with centripetal motion without knowing mass? (1 Viewer)

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#### Willywang

1. The problem statement, all variables and given/known data
you have a object hanging from your roof, once it reaches constant velocity, the diameter of its motion is .755m, and it takes 8.5 seconds to travel 10 cycles. the cord is .46m long

2. Relevant equations

what is the tension of the cord?
let alone, how do i find the mass of the object?

3. The attempt at a solution

i came up with the equation that T=mx(4)x(pie)^2 x (r)/P^2
but i have everything except for mass in order to solve this.

So..in an attempt to find mass...
i found velocity of the object travels at 2.78 m/s

with F=mv^2/r and A= v^2/r i can substitute F and A in F=ma

but when plugging in numbers, i find that M cancels out each other, leaving me with a dead end.

So, basically if someone can help me find the mass of the object i can solve tension myself

Thanks

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