Pendulum Velocity (changing w/respect to length)

[gjh]

I'm a little stuck on what happens conceptually with the velocity of a pendulum. To my knowledge, increasing the length of the string does increase the max potential energy (which is reached at the highest pt of the pendulum) and thus increases the max kinetic energy (which would in turn increase the velocity at the nadir of the pendulum swing -- the max velocity). However, this is where I get stuck -- according to this formula:

f (freq) = 1/(2pi) * sqrt(g/L), where L=length of the string

(I'm assuming freq is directly related to velocity of the pendulum), increasing L would DECREASE frequency (and therefore decrease the velocity). So is it that the velocity of the pendulum, when it's NOT at the lowest point, is decreased with an increased L? Am I missing something/is it wrong to assume freq = velocity?

Most of my confusion came from TBR Physics Section V Q#23 - "What is true of the velocity of a pendulum bob at its lowest point"?
A: It increases as the cord length increases, given the same initial displacement angle of the pendulum.
The book explains that v = sqrt(2*g*delta height) but that seems to go against the idea that increasing L (which increases delta height) would decrease the frequency, according to the above equation).

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[SpaceBuff12]

Frequency is not velocity. I think you are getting hung up on the idea that if there is a change in maximum velocity then there must be a change in frequency; this is NOT true. If you change the initial displacement angle the maximum velocity will increase, but the frequency of oscillation will remain the same. For the same displacement angle, the pendulum with a greater length will have a greater potential energy at its highest point and therefore a greater velocity at the lowest point.

 

[brood910]

Why are you saying velocity = frequency?
Is it because of v = f vs lambda?
If you are using this equation for pendulum, you are doing it wrong. This is only for waves.