Conductivity Tester With Light Bulb

Test some of the provided materials for conductivity by placing them between the two loose terminals.

Conductivity tester with light bulb.

The light bulb should come on. They learn the difference between conductors and insulators of electrical energy as they test a variety of materials for their ability to conduct electricity. Your conductivity tester is now ready to be used. I am using a simple 100 volt electrical conductivity device that was custom made to show the variance in conductivity in water and foods with a variance of differences in the brightness illumination or brilliance of the light due to the ionic mineral conductivity available.

However when solid nacl dissolves in water the sodium chloride solution lights the bulb brightly. If the light bulb glows brightly then the solution is very conductive. Gather different household items to determine if they conduct electricity. Touch the ends of wires to the different objects.

Write the names of the testing materials on the board and ask students to predict which ones are conductors and which ones are insulators. Observe the light bulb and record what happens. The maryland science center. Some examples of items to try are pencils paper copper screws screw drivers etc.

Fill a cup with salty water or other ionic solution and then rest the device on the rim of the cup make sure the aluminum leads are immersed in the solution. A light bulb conductivity tester does not light up at all when the electrodes are inserted into either solid granular sodium chloride or solid granular sucrose. When solid sucrose dissolves in water the sucrose solution fails to light the bulb. If the bulb lights you have completed the circuit.

This engineering curriculum aligns to next generation science standards.