A message from Junior Einsteins:
Wishing you and yours a happy and safe Easter weekend. We have put together an Easter STEM activity for you to enjoy at home. For those of you missing the science fun from Junior Einsteins Science Club® we have also included some suggestions for staying in touch below. Check out our online science club sessions 10am daily Booking essential!
Eggsperiment- spinning eggs !!!! From the outside, raw and hard-boiled eggs look just the same, but there’s an easy way of telling them apart without breaking them open.
You only need one hard-boiled and one raw egg. The eggs should be at the same temperature.
Ask the 'Junior Einsteins' to guess which egg is which (perhaps adding a mark to one egg to avoid confusion).
Take one egg and set it spinning quite fast on a hard surface.
Quickly stop it with a light touch, then quickly let go again. See whether it starts spinning again at all, or stays stopped. Try this a few times.
Do the same with the other egg.
You can tell which is the raw egg as this one will restart spinning slightly after being stopped.
The inside of the hard-boiled egg is solid, the raw egg is liquid inside. When the raw egg is set spinning and then stopped, the liquid inside it continues to move, which makes the egg start spinning again. When a hard-boiled egg is spun and then stopped, the solid interior does not continue to move, so the egg will remain still.
Scientifically, we think of this in terms of forces in a viscous (thick) liquid. When the raw egg is stopped by touching the shell momentarily, the liquid inside keeps moving, producing forces across the liquid. If the egg is quickly released, these forces can then act on the shell to make the egg move again. With the hard-boiled egg, there is no viscous liquid to store the force, so stopping the spinning brings it to a complete standstill.