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## Homework Statement

find the period with only using L (for the long of the rope), R (for the radius), M (for the mass), and G (for the gravity)

## Homework Equations

V=ωR

F

_{centripetal}= ##\frac {MV^2} {R}##

F

_{gravity}= MG

phytagoras

basic trigonometry

## The Attempt at a Solution

i have tried to do it this way

##x=\sqrt {L^2 - R^2}##

##F_1=F_2##

##MG Cos (θ) = \frac {MV^2} {R} Cos (90-θ) ##

##\frac {MGR} {L} = \frac{MV^2 \sqrt {L^2 - R^2}} {RL}##

##\frac {MGR} {L} = \frac{Mω^2 R^2 \sqrt {L^2 - R^2}} {RL}##

##\frac {MGR} {L} = \frac{M4π^2 R^2 \sqrt {L^2 - R^2}} {RLT^2}##

##T^2 = \frac{4π^2 \sqrt {L^2 - R^2}} {G}##

##T = \sqrt {\frac{4π^2 \sqrt {L^2 - R^2}} {G}}##

am i right?

some of my friend have i different answer from me, actually, i dont really know where is the centripetal force direction

can someone explain me what is centripetal force actually with answering this question

(sorry for bad english)