Alessandro volta

ALESSANDRO VOLTAALESSANDRO VOLTA

1

2

Alessandro Giuseppe Antonio Anastasio Volta was born in Como on February 18th, 1745.

In 1774 he became professor of experimental physics at the University of Pavia, a chair he occupied for almost 25 years.

In 1800, he invented the first electric battery, which produced a steady electric current.

In honour of his work, Volta was made a count by Napoleon in 1810.

He died on March 5th, 1827.

3

Metal rod

Insulating support

Metal leavesGlass container

4

5

The ELECTROPHORUSThe ELECTROPHORUS

6

Glass or wodden handle

Brass disk

Insulating support

Resin diskcloth

The electrophorus uses the principle of electrostatic induction, that is the redistribution of electric charges in a conductor caused by the proximity of an electricfied object.

At the beginning the two disks are beated to remove moisture; then the resin disk is rubbed with a cloth and so it electrifies.

the brass disk is placed on the resin one and the charges are redistribuited inside due to induction.

7

If you touch the plate with a finger or you connect it to the ground, the charges on the top face of the brass disk are dispersed into the enviroment and it remains charged in the opposte way with respect to the resin disk.

Now you can use the brass disk to make electrostatic experiments.

When the charge on the brass disk is exhausted, in order to have charges again, you can place the disk back on the resin support that is still thrilled and then you can repeat the process over again.

8

Volta studied gases and succeded in discovering the isobaric expansion of air law, estended later by Gay-Lussac to all gases.

He was also the first person to isolate methane and discovered that a methane- air mixture could be esploded in a closed container with an electric spark: this is the basis of the internal combustion engine.

9

Volta discovered that the electrical potential in a capacitor is directly proportional to electrical charge by the formula Q=CV where Q is the electrical charge, C is the the proportional costant called “capacity” and V is the voltage.

He also wrote about the capacitor he had constructed to collect and store electric charge, and how he had used it to study a variety of electrical phenomena.

10

11

12

13

14

Alessandro Volta’s statue in Como15

THANKS FOR YOUR ATTENTION

16