Questions on electricity were asked by Gavin (10), Tegan (10) and Hayden (9)

Gavin asked “Why does the energy flow through the wires?”

Tegan asked “How does electricity work?”

Hayden asked “How do batteries springs and wires make a complete circuit?”

So how does this compare with a modern day battery. lets have a look and think about Gavins question.

Hayden and Tegan. In the circuit below the  energy flows around the circuit when the switch is closed. Why? What are wires made of? What is special? If the wires were plastic do you think electricity would be able to pass through it? Try and make your own circuits with different materials.

Electricity is linked to the passage of negatively charged electrons. These were very comfortable in the battery until it was connected to a circuit (a circuit is a continuous pathway) and the switch was closed. The circuit gave the electrons (negatively charged) a passage to the positively charged end of the battery. Electricity (electrons) flowed and accompanying the electrons was energy. Look at the Science Master Special on Energy and why not try the Circuit Quiz.


Do not play with mains electricity. It is very dangerous and could kill you.

Sadie (8) asked “How do batteries work?”

Sadie, many thanks for your question. I asked my friends to help me…


Yes I remember doing that, it wasn’t easy but I did get the led to light up.

Let’s start with a possible definition of a battery – It’s a device that converts chemical energy into electrical energy. If you are uncertain about what I mean by energy then have a look at this site.  

Now why do we have two different metals? Inside the squeezed lemon is a lot of lemon juice. There is a chemical reaction between the metals and the lemon juice. Because the metals are different they react with the lemon juice in different ways. The different reactions give the copper nail a positive charge and the iron nail a negative charge.

Connecting the two nails together with a wire will give you a flow of electrons in the wire from the iron nail to the copper nail. This will continue until the chemical reaction inside the lemon reaches completion.

Your normal battery is like the lemon but obviously made of different materials. Look at the diagram below.

Sadie, I hope you have found this useful. If you or any other reader would like to make a comment please fill in the Leave a Reply box below. And if you are uncertain about bits of the explanation please ask another question.

Additional note …copper nails are difficult to get hold of so why not use a small piece of copper tubing. Also there is a small possibility that a battery was produced over 2500 years ago, see The Baghdad Battery. Ask your teacher about it. Or ask another question.

Abdur of 6K asked – If you had a solar powered light bulb and you were in a dark room, could you make a circuit with batteries and wires to make it work?

I asked my friends to look at this.

solar cell2

I liked the circuit that my friends made however ….just to let you know, the symbol for a solar cell is:

solar panel
Which one do you like, the one my friends used or the official one? You can vote by clicking on the Reply button below and giving me your answer.

The really testing part of this experiment is where will you put the switch to test that the solar cell, in the dark, is not making the bulb light up? Unsure – then