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MaZnFLiP

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**[SOLVED] Pendulum and Centripetal Motion Question**

**Picture and FBD**

**The Problem/Question**

Calculate the speed of a 2.0m length pendulum at the very bottom of the swing if you raise it a vertical height of 0.12m

**Relevant equations**

[tex] F_net = F_T + F_G = F_C = m(\frac{V^2}{r}) [/tex]

**The attempt at a solution**

Well, after looking over this problem, I think I'm doing something amazingly wrong.

Looking at My equations, I went from

[tex] F_C = F_T + mg [/tex]

to

[tex] m(\frac{V^2}{r}) = F_T + mg [/tex]

From there I got:

[tex] \frac {V^2}{r} = F_T + g [/tex] because the masses cancel.

Next:

[tex] V^2 = gr + F_T[/tex]

After finding [tex](-9.81\frac{m}{s}^2)(2.0m) = 19.62[/tex], I found the square root which was [tex] 4.429 \frac {m}{s}^2 [/tex]

The problem is that after looking at the answer sheet, The answer is supposed to be:

[tex]1.5\frac{m}{s}^2[/tex]

Could someone please help as to tell me where I went wrong?