Think for Yourself » Physics

Leaving Cert Physics notes updated

ozymandias1 — Sun, 22 Feb 2009 17:21:54 +0000

This blog has been fairly quiet recently; I have spent every spare minute updating the student notes on the website and feel very proud of my work. I don’t know if anyone else is going to notice mind, but then I guess that’s not the point.

For each chapter I have included all past exam questions, which can be cross-referenced with the relavant marking-scheme which is also included. Also included is a copy of the associated extracts from the syllabus – this gives the students the responsibility of checking up on me to ensure I have everything covered before moving on to the next chapter.

There is also plenty of “extra-credit” material tucked in at the end to help address many of the conceptual difficulties which students (and teachers!) have; these also help to set the historical and social context of many of the discoveries. Science is after all a very human activity, dispite what you might think from the text-books and syllabus.

I would hope that students outside of my own school would find these useful, particulary those who don’t have a specialised Physics teacher should find it to be a useful resourse to help them help themselves.

Some would see the decision to allow the students to see their test in advance to be somehow ‘cheating’, but for me it helps overcome one of the biggest obstacles facing many students who may not be in the top bracket; they simply don’t know what to learn. I have found with this new approach that hard-working students who are of average ability have gone from 50% to 75% since I introduced the option. It doesn’t change those at the top; the A-students still get their A’s, while at the other end those determined to do as little as possible still continue to achieve results which reflect this.

But I’m delighted with this practice. We spend at least one class and maybe two going over these questions at the end of each chapter and before I give them the test. Then I simply pick ten questions from the list, while altering the numbers in the maths questions. After seven years of leaving-cert questions (2002 - 2009) there is a pretty comprehensive bank of questions there, so I don’t believe it is giving students an inflated sense of their own worth.

But as an incentive to prepare for class tests and greater student participation it is working like a dream. I’m not too proud to say that I’m thrilled with my work!

Colours from black and white? Say it ain’t so!

ozymandias1 — Thu, 27 Nov 2008 19:29:07 +0000

We had half a class the other day so we just played around with some equipment left lying about.

One such piece was a cardboard disc with black circles and shapes on a white background. If you spin it quickly you get to see coloured circles! It’s mad I tell you.

Only thing is, because it’s got to be a psychological effect it doesn’t get picked up on the camera.

Hates that.

Unusual resource for explaining Joule’s Law

ozymandias1 — Thu, 23 Oct 2008 13:21:59 +0000

An offshoot of Joules’ Law is that when transmitting electrical power, the current is kept as low as possible in order to reduce energy losses associated with heat of the electrical cables. Because the power being transferred is the product of the voltage and the current, we can still get the same power transferred if we halve the current and double the voltage, or; make the current very, very small and make the voltage very, very big.

So power -lines transmit power at a voltage of up to 400,000 volts. Then, as the power gets closer to the home, the voltage is reduced in stages, and correspondingly the current gets increased. This occurs in appiances called transformers.

I came across a lovely interactive explanation of this when in honeymoon in Hong Kong.
I couldn’t resist.