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## Homework Statement

A pendulum consists of a bob of mass A hanging from a string of non-zero mass m. Its maximum displacement is p/4 [whatever that p means, I do not know. the question writers do a poor job of writing questions]. What is true of the tension in the string?

- 1) It is greatest at the top.

- 2) It is greatest at the bottom.

- 3) It is uniform throughout.

- 4) It does not vary when the pendulum is put in motion.

- 5) It is greatest when the pendulum is it its maximum amplitude.

## Homework Equations

No equations

## The Attempt at a Solution

I attempted this by putting down 2, but the authors believe it is 1.

Here's how I thought of it.

Sum of centripetal forces = m * centripetal acceleration

T - mg [at bottom, maybe I need a sine or cosine term to account for angle] = m (v^2 / r)

T = m ( v^2 /r ) + mg.

Thus, the T would be greatest at the bottom as the speed of a pendulum bob is maximum at the bottom [maximum kinetic energy], according to my logic. How does this work, why are the writers right, and why is my approach wrong?

Thanks in advance for the assistance!