Powered by MathJax From GCSE Maths, to Rocket Scientist...: March 2013

Monday 25 March 2013

Been Sick, But Back on Track

I'm a month or two older, since my last blog post and my daughter tells me that I have 6 new grey hairs too.  Well, I've had one of those times in the last couple of months, where a lingering winter virus has caused me to spend several weeks with a headache and not much motivation.

Having said that, I have continued with my S382 Astrophysics studies with the OU.

Chapter one was a challenge for me because I haven't done any University level 'sciency-stuff' for a long time and because my recent background has been firmly planted in pure mathematics, I have struggled with silly things, such as working out what units go with what quantities.  Is it banana-lengths per second, or Joules per gnats-whisker?  Who knows?

Anyway, In this last month, I have had one computer marked assignment and one TMA to write.  I managed 83% on the TMA, which was mainly based around working out energies involved in hydrogen burning stars, and the like.

The maths was very straight forward, but I did struggle with the descriptive essay style questions.  I stuck to what I knew and used as many formulas as I could find, to pad out my answers, which worked okay.  I didn't finish the last question due to time constraints, so I think I would have been on track for a +85%, had I finished it.

But, I didn't. However,I'm glad of a solid start.  I have finished 3/4 of the CMA, but I am struggling with it a little, as it is testing my non-existent basic science knowledge, which I am trying to dredge from my memory banks formed in the 1980's.  If only I had been more attentive in school!  But I wasn't.

Anyhow, this morning, I am working steadily on TMA02.  This is a liberal artists dream; lots of paragraphs, with the odd formula for decoration.  It is a very different TMA to the first one.  Verbose, yet devilishly difficult, in places.

I am about a week behind on reading the chapters, but I have a week to catch up over Easter, with ten days off work, so I am confident of keeping on track.

With regards to the debate that I was having with Duncan about 'why stars are hot'; I didn't manage to speak with a tutor about this matter; however, having studied the material, I can see that the stars get hot because they contract under gravity, which raises the pressure / kinetic energy of the stellar material, until it is hot enough to ignite hydrogen fusion.  Once the fusion begins, it acts to maintain that heat over the required lifetime of the star, until around 10% of the hydrogen has been burnt.  It then evolves into a different form, depending on its original starting mass.

So, I agree with Duncan, that the book was rather misleading as it didn't seem to put enough daylight between the terms 'hot enough to initiate fusion' and the subsequent maintenance of that heat/fusion over the lifetime of the star.

Astrophysics is difficult enough, without such supereminent elements of knowledge being shrouded in mild confusion by set texts.

I'll let you know how TMA2 goes.