# Monkey and Hunter Demonstration: An Interactive Example of Projectile Motion

## Document Type

Oral Presentation

SURC Ballroom A

17-5-2012

17-5-2012

## Abstract

Demonstrations have proven to be an affective instructional method while teaching many different aspects of introductory physics. This project was designed and assembled to be easily implemented in introductory physics courses. It demonstrates a classic physics example known as the monkey and hunter problem. The example revolves around basic kinematic concepts where the ideas behind projectile motion are applied to two falling bodies. A projectile is launched pointed directly at a hanging object in the distance. At the precise moment the projectile leaves the launcher the object it was pointed at is released and left to fall. Assuming the projectile was close enough to the hanging object so that they do not intercept the floor, the projectile and the object will always collide with each other. The demonstration was designed and constructed to recreate this phenomenon using a spring launcher, ball bearing, photogate circuitry, and an electromagnet to hold the hanging object. The construction used a variety of tools and materials including basic logic circuitry components to manage the release of the hanging object. The setup was then presented in an introductory calculus based physics course, where students filled out a worksheet before and after the demonstration so that comparisons could be made on how understanding was affected by what they observed. The comparison of worksheets established an overall improvement in understanding after having observed the demonstration.

5

## Faculty Mentor(s)

Bruce Palmquist, Greg Lyman

Physics

## Share

COinS

May 17th, 11:15 AM May 17th, 1:44 PM

Monkey and Hunter Demonstration: An Interactive Example of Projectile Motion

SURC Ballroom A

Demonstrations have proven to be an affective instructional method while teaching many different aspects of introductory physics. This project was designed and assembled to be easily implemented in introductory physics courses. It demonstrates a classic physics example known as the monkey and hunter problem. The example revolves around basic kinematic concepts where the ideas behind projectile motion are applied to two falling bodies. A projectile is launched pointed directly at a hanging object in the distance. At the precise moment the projectile leaves the launcher the object it was pointed at is released and left to fall. Assuming the projectile was close enough to the hanging object so that they do not intercept the floor, the projectile and the object will always collide with each other. The demonstration was designed and constructed to recreate this phenomenon using a spring launcher, ball bearing, photogate circuitry, and an electromagnet to hold the hanging object. The construction used a variety of tools and materials including basic logic circuitry components to manage the release of the hanging object. The setup was then presented in an introductory calculus based physics course, where students filled out a worksheet before and after the demonstration so that comparisons could be made on how understanding was affected by what they observed. The comparison of worksheets established an overall improvement in understanding after having observed the demonstration.