Electric generator

How can electrical devices work without batteries?

Difficulty:
Danger:
Duration:
15 minutes
Electric generator

Safety

  • Carefully review the general safety advice in the instruction book before starting the experiment.
  • Read the "Magnets and electricity" and "Working with batteries" sections of the safety manual carefully before proceeding.
  • Do not let children under 8 years old handle small magnets.
  • Disassemble the setup after the experiment.

Step-by-step instructions

The magnet and the wire will only interact when there is electric current in the wire.

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Let’s assemble a closed casing for the magnet that still allows it to move.

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The movement of the magnet inside the coiled wire creates electric current in the circuit!

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Let’s see whether the magnet’s movement is enough to light up an LED!

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Disposal

  • Dispose of used batteries in accordance with local regulations.
  • Dispose of solid waste together with household garbage.

Scientific description

Once you connect the wire to the battery , electric current begins to flow. Electrons  start flowing through the wire, creating a magnetic field, which in turn interacts with the inserted permanent magnet and holds it there!

Normally, a buzzer would only work when connected to a source of electricity. Curiously, in our setup, the buzzer somehow beeps without a battery! What happens when our permanent magnet moves along the wire circuit closed in a loop with just a buzzer or an LED, without any source of electricity?

Turns out, the moving magnet  affects the electrons  in the wire  and forces them to move along the wire! That’s how the electric current is generated in the wire. Such a setup is one example of electric generators.

Although there are numerous designs of electric generators, they all operate on the same principle. Such generators are used at hydro-electric, nuclear, and wind power stations and produce over 90% of the world's electricity.