1. Monkey and the Zookeeper

2. A monkey has escaped from the local zoo
A monkey has escaped from the local zoo. A zookeeper is sent out to rescue the monkey and return him to the safety of the zoo by tranquilizing him with a dart. The zookeeper tracks the monkey down and finds him hanging from a branch of a tree. This particular monkey has escaped several times in the past and has learned to drop from the tree as soon as the tranquilizer gun is fired.

3. The Problem – Where to Aim?

4. Setup

5. Motion Of The Dart
Y- direction
X- direction

6. Effect of Gravity If there were no gravity (g=0)
The dart would move along the hypotenuse of a right triangle. The -½gt2 in the y-direction indicates how far the dart is below the hypotenuse at any time t.

8. Motion of the Monkey
Y- direction

9. Dart Hits Monkey
The acceleration term on each side is the same. This is because the relative acceleration is zero.

10. Eliminate Time

11. Aim at the Monkey