UCSB Science Line
Sponge Spicules Nerve Cells Galaxy Abalone Shell Nickel Succinate X-ray Lens Lupine
UCSB Science Line
Home
How it Works
Ask a Question
Search Topics
Webcasts
Our Scientists
Science Links
Contact Information
Why do Boom Box speakers give out sound when they are across the room?
Question Date: 2003-05-20
Answer 1:

The concept behind a speaker is electromagnetism. Electricity is run through two coils, placed end-on-end to one another. This spiraling of electric current turns the coils that the current passes through into magnets. These magnets generate an attractive or repulsive force upon each-other depending on the relative directions of the current within them. Now, by rapidly adjusting the current, you can alter the amount of magnetic field, and thus the force, that the two coils exert upon each other. This means that you can rapidly move one coil, the "speaker", in and out of the boom box. As it does so, it displaces the air (if it is being moved out) or creates a vacuum (if it is being drawn in). This movement causes pressure waves - sound - to be formed in the air.



Click Here to return to the search form.

University of California, Santa Barbara Materials Research Laboratory National Science Foundation
This program is co-sponsored by the National Science Foundation and UCSB School-University Partnerships
Copyright © 2020 The Regents of the University of California,
All Rights Reserved.
UCSB Terms of Use