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Activities/Turtle Art/Using Turtle Art Sensors (view source)
Revision as of 01:15, 8 November 2010
, 01:15, 8 November 2010→Measuring Water Salinity
Small amounts of salt are added to tank water, bringing the resistance down from 5k ohms to 2k ohms. Salt added on two occasions
Small amounts of salt are added to tank water, bringing the resistance down from 5k ohms to 2k ohms. Salt added on two occasions
==Generating Electricity from a Changing Magnetic Field==
Requires a refrigerator magnet, often given away free with advertising on it.
Wrap 50 turns of insulated wire onto a nail and connect the two ends to a phono plug as shown (if it is a stereo plug, probably the red wire and the copper shield). Connect the phono plug to the microphone input. Graph the Sound or Volume block.
* Wipe the sharp end rapidly over the back of the fridge magnet, try both directions.
* Try a different number of turns of wire
* Try moving the nail more slowly, what happens?
* What is happening?
* Why does it work better on one axis of the magnet? (hint rub 2 magnets together)
==Links==
==Links==