Sometime last year we found out how good eggs were for us. Not only are they very nutritious but they are also good for our eyesight and for memory (maybe we should all chomp down eggs for breakfast when we are writing exams in future. (Here’s the blog link in case you missed it.
The other day I read about a cool trick that you can do with eggs. It’s really simple. All you need are two eggs. One you have to hard boil (make it 15 minutes to make sure) and once it’s been boiled, put it in the fridge so that it becomes the same temperature as the raw egg.
Now you have two eggs that look and feel the same. Nobody knows that there really is a difference.
This is what you do…
Spin the eggs and watch what happens.
One egg should spin while the other egg wobbles.
You can also lightly tough each of the eggs while they are spinning. One should stop quickly while the other keeps moving after you have touched it.
Ask your audience why they think this is happening.
And why is it happening…. the raw egg’s centre of gravity changes as the white and yolk move around inside the shell, causing the wobbling motion. Even after you touch the shell it continues moving. This is because of inertia – the same type of force you feel when you change direction or stop suddenly in a car – your body wants to move one way while the car wants you to do something different. Inertia causes the raw egg to spin even after you have stopped it, this contrasts with the solid white and yolk of the hard-boiled egg. It responds much quicker if you touch it.
This is a good eggsperiment to test a friend or someone in your family with – see if they can figure out how to tell the difference between the eggs (without smashing them of course) before showing them how your nifty trick actually works.
Then you can have a nice hardboiled egg sandwich!
Have an eggsellent week!