Free Science Videos and Lectures

Walter Lewin Makes a Battery out of Cans and Water

The best physics lecturer Walter Lewin makes another wonderful physics demonstration after having read a lecture on batteries.

The battery he creates has a huge potential difference - 10 to 20 kV!

You'll never believe what it's made of!
It's made of two cans with bottom and top open and two other cans. And then water is let to drip through the two open ones.

After a short period a spark comes up, then another one, then another one.

Do you know how it works? If not, see the free electricity and magnetism video course by Walter Lewin at MIT's OCW!

This science video contains:
experiment, current, walter lewin, physics, demonstration, battery, emf, polarization, hydrogen, potential, sparks