WOW experiment of the day: The lemon battery!
We tried to make a light bulb light up using nothing but lemons, copper and zinc. Unfortunately, it didn't work and we asked ourselves lots of questions about why this might have happened and the aspects of the experiment we would have to check and control. Here's one that did work!
Q Why is the Earth round?
A Gravity is the cause. It pulls everything together. The more mass an object has, the more it will pull all of its parts to the centre.