P2_14 Shotgun patterns

This article provides a model of particle collisions for producing shot patterns from shotgun ammunition of a constant mass, for different numbers of pellets. The scatter pattern is found to be Gaussian, and the mean deviation for pellets from the centre increases linearly with range. Interestingly, this deviation is slightly greater for fewer large pellets, than the same mass of smaller pellets

P2_7 Power Curves and Gear Ratios in Bicycles

This article investigates how the power exerted by a cyclist varies with cyclist speed, and gear ratio. From Hill’s relation, both relations are determined and plotted. Suggestions are made on how these results might be useful to recreational and competitive cyclists

P2_3 A Tapered Tower

This paper evaluates the possibility of building a space elevator from a mechanical standpoint; calculating the yield stress and required density of a homogeneous material that such a structure would ideally need. It is concluded that a tapered tower made from carbon nanotubes may potentially be feasible

P2_13 Dominoes and Self-Organised Criticality

This article presents a very simple model of self-organised criticality using a 1 dimensional system of dominoes. It is found that when the likelihood of a domino falling is small, a power law exists between number of dominoes which fall in each event, and the frequency with which it occurs. This is determined to be of the form y=x-1.88

P2_4 Electromagnetic radiation from Mobile Phones

This paper demonstrates a method to quantify the energy absorbed by the human brain from using a mobile phone. Our results show the energy absorbed per second by a human head is PAbsorbed = 4.00 x 10-5 J.s-

P2_11 Fuselage Holes

This article looks at how long it would take the air to evacuate an aeroplane if the fuselage developed a hole, imposed under incompressible constraints. We find that the time for depressurisation, as a function of hole size, follows a linear, inverse power law. Â

P2_15 Quantum well widths as a function of doping

We iteratively calculate theoretical data within an infinite model, that allows you to determine the required well size given a specific doping, for a laser semiconductor emitting light between the wavelengths of 450 nm and 550 nm

P2_12 InGaN quantum-well width w.r.t λ

We derive a value d=2.49 nm (3 s.f.), the required InGaN quantum well width, to produce a ‘true’ green laser of ~530 nm, using a simple infinite well model. ‘True green’ semiconductor lasers are the next generation of lasers for use in HD disc-reading devices

P2_10 Shotgun!

This paper looks at the stopping power of shotguns as a function of distance from the target and number of shot in the shell.  This relationship is determined, and it is found that the stopping power falls off quickly for larger numbers of pellets. Avenues for a more thorough investigation are also suggested