Physics lesson with Daddy

Alicia can only have Physics lessons with daddy coz mummy's not very gifted in that aspect. :P hehe.

After Alicia got tired of scooping and funnelling, we moved on but daddy suddenly had the inspiration to show Alicia physics phenomena in every day life.

Pressure

1. Fill a bottle of water with some water then turn it upside down, partially submerged in a basin of water such that the bottle doesn't move. The mouth of the bottle should be touching the base of the basin.
2. Get your tot to try to lift the bottle.
3. She will feel some resistance while trying to lift the bottle our of the water.

Reason:
As the bottle is lifted up but still with its mouth in the water, the pressure inside the bottle reduces. This compresses the air inside the bottle and a "partial vacuum" is created. Since the pressure inside the bottle is now lower than atmospheric pressure, the water is kept inside the bottle by this pressure difference. Hence some significant force is required to pull the mouth of the bottle out of the water. This force will be greater if the mouth of the bottle started deeper in the basin of water (as a larger pressure difference can be built up).

Resonance

Fill a wine glass with some water:

Moisten finger slightly then glide finger along the top of the glass: this will generate a sound.

Reason: 

This is a simple experiment commonly shown. The continuous rubbing of the brim of the wine glass causes the wine glass to vibrate, which in turn causes the air column in the wine glass (above the water level) to vibrate.. This vibration of air molecules is actually sound wave in air! The faster your move your finger, the higher will be the frequency of sound produced. As you vary the speed of your finger, you will notice that at a particular range of speeds, the frequency of sound produced will be such that a "stationary wave" is formed in the air column. This results in increases amplitudes of vibration of the air molecules, hence causing a much louder sound to be heard (or resonance).

Alicia learning about resonance

Well, you don't have to explain in such difficult terms to a young tot. We obviously didn't; we merely got her to experience the phenomena. Explanations can wait till she's older... :P

I hope you have fun! :)