Safety: There isn’t really any danger in this experiment however I will make sure my fingers are safe from the different weights.
Method:
- Put a pin in a block of wood.
- Tie a rope around the pin.
- Pull the rope with a Newton meter. Note the force needed to move the block.
- Increase this force until the block moves at a constant speed. Note this force.
- Repeat the steps three times and find an average static and sliding friction for a certain weight of the wood.
- Increase the weight by 1N and repeat. Do this until the weight on top of the block is 10N.
Diagram:
Force
Results Table:
Conclusion: In conclusion, we can see that more weight means that more force is needed to move an object. This is seen on the graph because as we move further right (more weight) then more force is needed. The graph goes up at a slow, constant rate and then begins to curl upwards, suggesting acceleration. The results prove my initial prediction that increasing the weight of an object will increase the force needed to move it due to the force of friction between the bottom of the wood and the table.
Evaluation: I think that the experiment went well. I followed the steps suggested in my method and kept everything fair. I believe my results were quite accurate because I repeated the method 3 times before finding an average. There were however some odd anomalies such as a surprise 1.2N sliding friction of a block with a weight of 7N. I think these anomalies were due to numerous reasons. Firstly, I believe that the laboratory was unsuitable for this experiment, because the workbenches had holes in them, graffiti and had been varnished. Therefore, with increasing weight, the bench would become slightly adhesive and therefore it wouldn’t be friction causing a higher force to be needed to move the wood, it would be the varnish. This was visible when the weight of the wood began to exceed 8.5N and on the graph the line begins to curl upwards showing this theory.
I also think that the method was faulty and if improved could provide us with more accurate results too. I think using a pulley instead of a Newton meter would have roduce more accurate results and also made the experiment easier and quicker. When Newton meter pulls an object, the person pulling it may be distracted or may presume a result that may not be true. It is also very difficult to read off a Newton meter. However, due to poor school funding for science, there is a lack of apparatus and therefore this may have not been possible. I think that to make sure that these results are reliable, we must cross-reference this experiment with one similar. This will create more useful evidence to fulfill the aim of our investigations.
Despite this, I still believe my results provide us with reliable enough evidence for me to support both my conclusion and prediction and do show that increasing the weight of an object means that more force is needed to move it due to the force of friction.
