Last Thursday was the deadline for the first draft if the EE. All of my students managed to hand in a first draft (they didn't have a choice) so I thought I would update on their progress.

Emil

Emil's research question concerns the relationship between the damping of the oscillations of a floating cylinder and the viscosity and density of the fluid. The title of his essay is "Dragged down" haha. Emil had some problems getting the floating cylinder to float vertically but manage to solve the problem by adding weight on a rigid extension. He has also had some problems with his theoretical model. "I believe I have found that the aspect of the theory where I chose the diameter of the cylinder as the characteristic length for calculation of the Reynold's number is incorrect, it should be the length of the entire cylinder. This causes my theoretical results to be very different, and not very well at all with the experimental data, and so I am not completely sure what to do about it. I will have to look over this for the final draft, hopefully the rest of the EE still carries some relevance."

Hamza

Hamza ia investigating the motion of water coming out of a vibrating jet. This is a 3 dimensional projectile motion problem. The parabolic trajectory in the x-y plane is the same as a standard projectile but the z-y plane is a bit more complex. The range being related to the velocity of the jet. This varies sinusoidally resulting in a wave pattern. He has considered many different research questions but has settled on The relationship the frequency and amplitude of the sine wave formed by the water projected from a vibrating jet. One complication, and there have been many, is that the amplitude of the jet is not constant, it gets less as the frequency increases.

Era

Era is researching the history of Astronomy to see if she can do better than early astronomers. There are many possible angles she could take but my favorite is to focus on the question: "Did the invention of the camera have a greater impact on astronomy than the telescope". The telescope made it possible to see more but the camera enabled the view to be recorded so that changes in brightness and position could be more easily recorded.

Jet

Well Jet just had to do her EE on water jets and she hasn't regretted it. The problem she is investigating is related to the irrigation of tulip fields in the Netherlands, where she is from. It's quite nice when the topic has some practical application and even nicer when it has some connection to a students country of origin. The research question is "What is the relationship between the spread of a water jet and the angle of projection." She has tried several different theoretical models which all agree with her practical measurements that the optimum angle is 50°, neat.

Nejra

Nejra is trying to find out if there will be a PD across an accelerating conductor. The idea is that if a conductor accelerates upwards the free electrons will behave like the atoms of a gas and move to the bottom. This will cause a PD between the bottom and the top. To measure this effect she is using a rotating Hall probe which is wire conveniently however the hall probe is usually used to measure magnetic field so is affected by the Earths magnetic field. This causes some complications but they are not insurmountable. Unfortunately calculation shows that the PD for attainable accelerations is way too small to measure but that doesn't mean that she can't get a good essay out of it.

Vihaan

Vihaan is doing one of those "I never thought about that" EE's. When you pluck a string it forms a triangular pulse but when you draw the wave it is sinusoidal. How does the triangle turn into a curve? The best explanation is that the triangle is the sum of many sine waves but after a short time the higher frequencies are damped out leaving just the lower harmonics. Vihaan measured this effect using a small magnet attached to an elastic string. I spoke to a musician friend about this and he confirmed that it is a known phenomenon that if you remove the first part of a guitar note you can not tell it is a guitar because it is the first part that contains all the characteristic harmonics. I didn't know that and he didn't know why, now he does.

To be continued