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Electrical Current
Two Italian scientists - Luigi Galvany and Alessandro
Volta - made important discoveries about electricity in the late
1700. Galvany hung a dead frog on an iron hook and touched the
frog with a copper wire. The frog moved. Volta proved that the
electricity that made the frog jump came from the wires - not the
frog. The frog’s muscles served as a conductor, a material that
allows electricity to pass through it.
A conductor is a material that allows electrons to flow
through it. An insulator is a poor conductor.
After Volta discovered that two metals that are separated
by an acid could create electricity, he built a machine called the
voltaic pile, or simple dry cell. The machine created a current, or
steady flow, of electricity. Then, a few years later, the English
scientist Sir Humphry Davy stacked several voltaic piles and
created the first powerful battery.
Comprehension Questions
I. Say which of the following statements are false and
which are true. Correct the false statements to make them
true.
1. They made important discoveries about electricity in the
late 1800s.
2. The frog’s muscles could not serve as a conductor.
3. A conductor is a material that allows electrons to flow
through it.
4. Two metals separated by an acid cannot create electricity.
5. The English scientist Sir Humphry Davy created the first
powerful battery.
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