By Ivan Cocklove
Design
Defining the problem and selecting the variables:
I will investigate how the height from which a mass falls onto flat surface of sand affects the radius of the crater formed as a result of the impact.
The height from which the ball is dropped is affecting the speed at the impact because the higher the drop, the longer the ball will have to accelerate, therefore the higher the velocity at the impact will be.
The formation of craters is observed in meteorites colliding with surfaces of space bodies.
When looking at the earth previous research shows that the diameter of the crater is proportional to the energy of the meteor raised to the power of .59. It is unlikely for the experiment to have the same proportionality as suggested by the University of Bristol. Firstly the ball s dropped from small heights.
Secondly it doesn’t heat up as much as a meteor going through the atmosphere and therefore its total energy is very different to the one in research discussed above. I do expect the diameter of the crater to get bigger the higher the velocity at the impact, but it will be a very different power coefficient.
The independent variable in the experiment is the height from which the ball is dropped. It is the distance from the surface of the sand to the point at which the ball is released from rest. The dependant variable is the diameter of the crater formed. The circumference of the crater will be assumed to go along the highest point of the upturned sand around the indentation (figure 2).
The controls for this experiment will be the amount of sand in the tray, arranged so that it is compacted and has smooth, flat surface parallel to the surface of the work station on every repeat.
Another control is the mass and shape of the ball dropped. Final control is approximate landing position of the ball being the