Tin Can Speaker

Another in a series of experimental web based science activities

Copyright 1998 by James P. Riser


Information: In this lab activity you will be presented with the opportunity to:

The materials:

As you can see in the image to the left, the materials are simple and inexpensive.

You - as a team - are to provide your own tin cans and button magnets.

In addition to the tin can and button magnet a mini-phone jack with wire leads is needed. Some enamel coated wire is used to wind the coils. And some tape holds everything to the bottom of the can.

 

 

A close-up of the copper wire coil and magnet taped into position on the bottom of the can is shown at the right. Start with 30 turns on your small copper wire coil. This you can vary later.

 

The mini-phone jack plugs into the headphone socket on a small transistor radio.

 

 

The VU Meter (Volume Units) of an old tape recorder is used to measure the volume generated by the speakers. Nothing needs to be tape recorded, you are merely using the meter for taking measurements. These measurements will need to be recorded on a data chart of your own design.

All equipment is crude, cheap, and available at most schools.

 

 

 


Variables and Record Keeping: As a research team, you will need to determine what variables might be manipulated to improve the quality of your tin can speaker. Once your team has determined which variables you will be changing, you need to design a data chart to record the VU's for each variable change you try. It is a good idea for you to subjectively evaluate and record on your data charts the "quality of sound produced". The loudest speaker might not be the "best".

Conclusions: From your team's experiments, you are to construct the best speaker possible (based on your research team's criteria) and demonstrate this speaker to others in the class.

Write up: As a team, write up your experiments in standard scientific lab format. Be sure to include your data chart and any graphs you might have made. Demonstrate your tin can speaker to your instructor.