What Angle Does a Pendulum Form When It Stops?

[ThatDude]

Homework Statement

A 2 meter long pendulum passes its lowest point with a velocity of 4 m/s, then swings back up before temporarily coming to a stop. What angle does it then form with the vertical, if the air resistance is negligible?

2. The attempt at a solution

I know that the kinetic energy at the bottom will equal the potential energy at the top - that is when the pendulum comes to a temporary stop.

KE = PE

(1/2)(m)(16) = (m)(g)(h)

h = 0.82 meters

Now, I understand that this is the max height above the lowest point.

I can't figure out how to proceed from here. I don't have two components to find the angle.

 

[Panphobia]

Actually you do have two components, you have the height at the instance where it is coming to rest, and you have the radius of the pendulum.

 

[ThatDude]

Actually you do have two components, you have the height at the instance where it is coming to rest, and you have the radius of the pendulum.

I don't quite follow.

 

[mfb]

The vertical, dashed line is the radius as well.
What happens if you add a horizontal line at the height of your object?