Question

How can you determine the max speed of a Pendulum?

Answer 1

Hi.

You would need the initial displacement in vertical height or degrees (so you can work out height given the length of the pendulum). When you have the height difference from the lowest point (where speed is highest) to the highest point, you use conservation of energy and set\[mg \Delta h = \frac{ 1 }{ 2 } m v^{2} \]
There is another alternative, but does that help?

Answer 2

initial displacement means maximum displacement*

Answer 3

delta h is the vertical difference between the starting point and the point of interest, here the bottom of the arc.