Marbles and Friction!

As part of a science unit looking at aspects of the physical world (force, motion, gravity and friction). Today we conducted an experiment to test which different surfaces had the least amount of friction, causing the marble to move/roll the fastest. We tested 8 different kinds of surfaces and measured how fast it took a marble to roll a meter on the different surfaces.

After conducting our experiments we analysed our data and drew conclusions about which surfaces contained the least amount of friction. 

We found that between all of our results were a large number of inconsistencies, causing people to gain very different results. From these, we discussed and learnt about whether our experiment was a fair test (we decided it wasn't), what variables are and how the difference in variables can create inconsistent results. 

We decided that the contributing variables impacted our results and created the inconsistencies between groups:

• Timing not reliable enough/not quick enough
• The force not being measured and being different every time for every person
• The angle of the surface varied
• students tested different objects, rather than all the same
• The strategies (1 flick or multiple) students used varied between groups

From this we have learnt a lot about fair testing and changing variables. We will be able to take this learning and create a test that would be fair and that would allow us to gain more consistent, accurate results.