A pendulum consists of a small object hanging from the ceiling at the end of a string of negligible mass. The string has a length of $0.75 \mathrm{m}$. With the string hanging vertically, the object is given an initial velocity of $2.0 \mathrm{m} / \mathrm{s}$ parallel to the ground and swings upward on a circular arc. Eventually, the object comes to a momentary halt at a point where the string makes an angle $\theta$ with its initial vertical orientation and then swings back downward. Find the angle $\theta$.