piezo electric sensor

A sensor is a converter that measures a physical quantity and converts it into a signal which can be read by an observer or by an (today mostly electronic) instrument

A piezoelectric sensor is a device that uses the piezoelectric effect to measure pressure, acceleration, strain or force by converting them to an electrical charge. The prefix piezo is Greek for 'press' or 'squeeze'.

http://en.wikipedia.org/wiki/Piezoelectric_effect

http://en.wikipedia.org/wiki/Pressure

http://en.wikipedia.org/wiki/Acceleration

http://en.wikipedia.org/wiki/Strain_(materials_science)

http://en.wikipedia.org/wiki/Force

http://en.wikipedia.org/wiki/Electricity

Piezoelectricity is the electric charge that accumulates in certain solid materials (such as crystals, certain ceramics, and biological matter such as bone, DNA and various proteins)in response to applied mechanical stress.

http://en.wikipedia.org/wiki/Electric_charge

http://en.wikipedia.org/wiki/Crystal

http://en.wikipedia.org/wiki/Ceramic

http://en.wikipedia.org/wiki/DNA

http://en.wikipedia.org/wiki/Protein

http://en.wikipedia.org/wiki/Stress_(physics)

PIEZOELECTRIC SENSORS BREADBOARD WIRES RESISTANCES RED LED SOLDERING MACHINE

THE BLINKING OF THE RED LED IS DUE TO “PIEZOELECTRIC”

EFFECT AS DISCUSSED EARLIER.

ON MAKING PROPER CONNECTIONS ONE CAN NOTICE THAT AS THE SENSORS ARE PRESSED AND RELEASED CONTINUOSLY,THE LED BLINKS.

THE LARGER THE PRESSURE APPLIED THE LARGER WILL BE THE CURRENT AND HENCE LARGER WILL BE THE INTENSITY OF LIGHT PRODUCED.