Thursday, 7 April 2016
Floating and sinking science learning
This week we have done a lot of learning about the reasons things float or sink.
We have discussed terms such as: displacement, volume, mass, and density.
On Tuesday we tested how much water is displaced by floating objects. We put items into a cup of water and measured the difference from the starting point. This difference is the amount of water that is moved, or displaced, because something else is filling in that space. Have a look below for some pictures of our testing.
We found that the heavier a floating object is, the more water it displaces. But what about sinking objects?
On Wednesday we measured the weight of objects that float and sink and compared that to the weight of the water that was displaced.
We found that when the weight of the water being displaced was the same or more than the object, it floated. When the item weighed more than the amount of water it displaced it sunk.
On Thursday, we discussed what density was and how it relates to floating or sinking. We found that the more dense something was, the more likely it was to sink. We also found that by trapping air we can reduce the density of an object, like how ships can float even though they weigh thousands and thousands of kilos.
Next week we are going to try our boats again and see if we can improve the design to hold more marbles!