Forces in Class 4
07 Jul 2021
This week, we have been focusing on water resistance in Science. We began by creating three different 3D shapes, a sphere, cone and cube, out of clay. We had to ensure that the mass of the objects was the same. We then timed how long it took for them to fall through water in a measuring cylinder. This allowed us to understand the importance of streamlining, and the impact of water resistance on an object in water.
We found that the cube fell the slowest due to its larger surface area allowing water resistance to have a greater effect. Dependant on which way up we dropped the cone, the cone or the sphere, were the quickest to fall due to their streamlined shape.
We then used what we had learnt to design a boat out of junk modelling materials. The aim was to design a boat that would travel the quickest through water. For it to do that, the children thought about the shape so that it was streamlined, and then ultimately the effect of water resistance is less. The children worked in small groups for this task.
The children then worked in their groups to build their boats. They really enjoyed this part of the task.
The children were all really proud of their finished products, as they should have been. Some were more boat like than others!!
Finally, it was time to test out the boats! Which would be successful? Which would move through the water the easiest? Would any sink?
In fact, they were all successful. They all floated although some for longer than others! They all moved in the water although some faster than others. Some were a little heavier on one side more than the other, but generally, they all did well.
Most importantly, the children understand how to reduce the impact of water resistance and the value of having streamlined shapes.