Why are wires metal on the inside and coated with plastic on the outside?
Build your own circuit to find out.
Which materials let electrons flow freely and which do not?





the matching image on the next slide.









Let's find out.






band
battery





leads




are called test leads.
alligator clips. What happens?




If they do touch, the light will shine
NO MATTER what you put into the circuit.












Test the objects
in your kit.
from the things that don't.














conduct electricity.
The wax in the crayon is an insulator.
does not conduct
electricity. Rubber
is an insulator.
on the wire is an
insulator too.










