If you have been following recent posts in this blog, then you’ll know Leyden capacitors are a hot topic here. That’s right they are capacitors, and in fact they were the first ones that ever existed. So we decided it was a time to explain how to build a Leyden Jar at school or in your bedroom. It’s always a good idea to have an adult sharing when you experiment with electricity.
Simple Stuff You Need to Build a Leyden Jar
You will need the following kit to build a Leyden Jar and commission it:
- Two pieces of new kitchen foil – these are the capacitor plates
- A medium size glass jam jar with lid – this will be the dielectric
- Two short pieces of insulated electric wire with both ends bare
- Some universal glue that sticks to both glass and kitchen foil
- A small amount of electrician’s tape – it should be brand new
- Electric drill and bit – or hammer and nail – to make a hole in the jar lid
Steps to Follow to Build Your Leyden Jar
Make sure the jam jar is clean and dry. Cut suitable pieces of kitchen foil to line the inside and outside. Glue these in position. Wait until the glue is dry and they are firmly fixed. Then tape one bare end of one electrical wire to the foil on the inside, making sure of a good electrical contact.
Make a hole through the jar lid. Pass the other end of the electrical wire through it, and take up the slack gently. Screw the lid down carefully. Tape one bare end of the second piece of electrical wire to the outside of the jar. You now have a Leyden jar capacitor, but you need to charge it.
Hold the jam jar with one hand. With the other, grip the wires so the other exposed ends are a short distance apart. Walk across a carpet wearing socks, to generate electrostatic energy.
Your simple capacitor will build a charge until this is sufficiently strong to jump between the exposed wires, and discharge. Repeat this exercise as many times as you like, but remember to keep your hands away from the those bare wire tips to avoid a small shock!
More Information
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