Leaving Cert Phyics

My contribution to Science Week – I thought I might teach some physics

At 40 mins long it’s not going to go viral anytime soon. It’s the middle 40 minutes of a double class but in it we managed to learn about some of the following:

The structure of the atom.

We, and everything around us, are mostly empty space.

We discovered that the appearance of  ‘solidness’ is an illusion – which lead to a  discussion about how light works.
We learned that there is a cultural aspect to what we see (and you definitely won’t find that in physics textbooks) and that Newton himself was subject to this and it resulted in him making a boo-boo that still goes uncorrected right up to today.

We discovered that electrons are constantly cascading down along everything we see in a seemingly never-ending avalanche, powered by energy from incoming light (so when this power source disappears, the electrons no longer have energy to jump up or fall back down, otherwise known as darkness).

We learned why things feel solid – all to do with the force of repulsion between electrons at the surface.

We developed a deeper understanding of Newton’s Third Law.

We discussed the fallacy of language – know the word for something (like gravity) and understanding what gravity actually is are two very different things, and shouldn’t be confused with each other.

We discovered that physics teachers don’t have all the answers, and should never pretend otherwise.

We were reminded that because almost none of the above is in the syllabus, the syllabus is a disgrace. It’s no wonder students don’t see the point of it.
There were 22 students in that class and the discussion could have gone on and on – I had to kick them out the door.  One can only imagine the conversations they must have had over the dinner table that evening.

If only all those who make such a fuss over Science Week could put a fraction of that effort into making the school syllabus a source of wonder and curiosity instead of what it is – a series of dull as dishwater facts which are to be merely learned off by heart.


The g-ball: a nice alternative to the traditional experiment

Setting up the apparatus for the Leaving Cert Physics experiment “Measurement of acceleration due to gravity using the method of freefall” can be tricky at best.
I recently ordered something called a ‘g-ball’ from ibotz for about €40 which does much the same thing. And at that price you could probably get a few of them and have different groups doing it separately.

The link below is a video of the g-ball in action.

There are all sort of errors involved, but it’s still reasonably accurate and errors can often serve to act as source of further discussion.

I like it in that it takes away all the confusion associated with the traditional circuit which I think distracts from the important physics (drop a ball; measure time of fall and distance traveled and from this work out g using a very simple equation).

If I was setting up a lab and trying to save money I would use the g-ball instead of the traditional set-up (while still ‘learning’ the traditional set-up for exam purposes).

To order the g-ball contact the boys at ibotz.com
Oh. And did I mention that it’s fun?
Physics? Fun? Who’d a thunk?

By the way, this is the traditional method:

Mr Devitt teaches us about Light

Jerome Devitt (History Teacher) runs a transition-year module on Light and Sound for theatres, and kindly agreed to allow us in to watch him teach one of his lessons.

Not all of it comes out great on video, but it should still prove very usefull for Senior Phyics classes.

If you would like to play with a virtual version of this, where you can control the postion and intensity of the lights, click here.

Thanks Jerome