Science Focus: Floating and sinking
Science Focus: Floating and sinking
Today we will be focusing on Floating and Sinking.
Every morning after we do our dishes my kids help me to clean up and put everything away. But this particular day my daughter threw her whole bowl of Otees in the basin. This led to my son asking why does the Otees float but her bowl sink?
Lucky for us it was a very cold morning, reaching below zero temperatures. So we could stay inside and do a lot of fun experiments.
We first did a couple of experiments before we got to the science bit.
Experiment 1: Making an egg sink or float.
You will need the following:
- Two tall glasses, half full of water.
- Two eggs
- Sticks
- Salt
Instructions:
- Place the two glasses on the table and throw some salt in only ONE of the glasses.
- Place a note at each to be able to identify which one has the salt in and which one is just water.
- Place a piece of stick in each. In which one does the stick sink or float.
- Take the sticks out and then place the eggs in. In which one does the egg sink or float.
Video about the egg floating in Saltwater by Kidish
Video by Kidish
Experiment 2: Try and test which items can sink or float
You will need the following:
- Kitchen Scale
- A small piece of clay
- Light candles
Instructions
- Place the small piece of clay and the light candles separately on the scale.
- The wax must be heavier than the candle.
- Place both of the items, at the same time, on the water.
- Which one sinks and which one floats?
- Why do you think do the one float and the other one sinks?
Conclusion
Let the children experiment and tell you what conclusion they have made.
Items that were placed in the water with salt in float, and items in the water without salt sinks. The salt increases the density of the water and then in return allows the object to float and not sink completely.
In some experiments, like the experiment with the clay and the candle, we don't add salt. Here we can see that the density of the clay is a lot more than that of the candle which causes the clay to sink and the candle to float.
