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Podcast on Leaving Cert definitions

Defintions

After taking so much time to put the last podcast together on neutrinos and then post about it, the hosting site Podomatic went down for maintanance for 24 hours. So I don’t know how that affected your feed, but if you got nothing then for once it wasn’t my fault. Unless the reason it went down was as a result of something I did, which would be impressive even for me.

Another possibility is that I after I uploaded the podcast so many people tried to gain access at the same time that the server just couldn’t handle the traffic 🙂

In which case a lot of people are in for a disappointment with this one. It consists of physics definitions which have appeared on leaving cert exam papers going back to 2002. When the new syllabus first appeared we were told that there was going to  be less emphasis on learning stuff  ‘off by heart’, particulary in relation to definitions. In practice this may well have been the case, the problem however is that because some definitions still appear, students have to cover all definitions to ensure they know the few which come up.

The syllabus is also unhelpful in that it’s not at all obvious what constitutes a defintion, but perhaps when the new syllabus comes out (in the year 20??) it may be more clear.

Apparently over 200 people have subscribed to this podcast, and that was after only two uploads, one of which was put together by two students.
One question: Why?

I think some people who were hoping to be entertained are going to be sorely disappointed with this one. No chance of it going viral then. It will be interesting to see if students find it useful. If you are a student don’t be afraid to let me know how I can improve.

I have put a link to both the podcast and the script on the Leaving Cert Revision page of thephysicsteacher.ie

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Dissection – great fun entirely

I have been experiencing a renaissance in my teaching life ever since I decided to embrace my ignorance on all issues biological (still can’t learn to love Chemistry unfortunately, but there may still be time).

We did heart dissections the other day.

I spent an evening searching for related videos on youtube. I am a firm advocate of the notion that unless you have been ‘prepped’ in terms of what to look for,you may well end up looking at an amorphous mess. In other words both the student and the teacher can be looking at the same object and see two completely different things. Discovery Learning obviously has its place, but as a teacher it’s all about knowing when to mix and match.

As usual there was a lot of sifting to be done before ending up with final list. As always, this is a labour of love.

Along the way I picked up the following nuggets:

  1. Each day your body makes 200 billion new blood cells.
  2. White blood cells live for two weeks, Red blood cells live four months.
  3. You have about 5 litres of blood in your body; when you donate blood you are giving up about half a litre.
  4. Your heart pumps about 70 times a minute, which equates to over 100,000 times a day!
  5. When exercising your heart-rate doubles to about 140 times a minute.
  6. Your heart is about the size of an apple.
  7. Blood takes about 35 seconds to make a round trip when relaxed, or 15 seconds when exercising.
  8. Heart Disease is Ireland’s number one cause of death.
  9. Irish women have almost twice the rate of death from heart disease as the EU average.
  10. The difference between a Heart Attack and a Stroke:
    Both are a result of blocked arteries: In a heart attack the blocked arteries are feeding the heart muscles, and those muscles are not getting the oxygen and nutrients they need to function.
    With a stroke, the blocked arteries are in the brain, and those brain cells are not getting what they need to function… depending on where in the brain it occurs, different functions are affected (e.g., speech, writing ability, and so on…)
    A third place where blocked arteries occur is in the lungs… then it is called a pulmonary embolism.

Ms Salter gave me a crash course on the dissection itself the day before, so I knew just about enough to set the troops on their way. They had an absolute ball, so why is this not a  mandatory activity? Why should non-specialist teachers like me get away with not doing such a memorable activity with my students?

I have since been informed that we can get hold of hearts which have all the tubes coming out of them, which should be much more educational.
I did tape the students doing the dissection itself, but accidentally taped over it. Sorry!
If doing it again I would  tell the students that their task is to teach another group about what they have learned. It tends to focus the mind!

I have put the youtube links on my website here.

Neutrinos, John Updike and Cosmic Gall

I’m suspect it may not have been part of his overall plan, but the death of John Updike coincided (can I say ‘nicely’?) with our class on Neutrinos.

There are some strange particles out there, but not many as strange as the neutrino.
Here’s what the syllabus has to say on neutrinos:

If momentum is not conserved, a third particle (neutrino) must be present.

And that’s it.
Here’s what Updike has to say.
This is why scientists need poetry.

Cosmic Gall

NEUTRINOS, they are very small.
They have no charge and have no mass
And do not interact at all.
The earth is just a silly ball
To them, through which they simply pass,
Like dustmaids down a drafty hall
Or photons through a sheet of glass.
They snub the most exquisite gas,
Ignore the most substantial wall,
Cold shoulder steel and sounding brass,
Insult the stallion in his stall,
And scorning barriers of class,
Infiltrate you and me! Like tall
and painless guillotines, they fall
Down through our heads into the grass.
At night, they enter at Nepal
and pierce the lover and his lass
From underneath the bed-you call
It wonderful; I call it crass.

Telephone Poles and Other Poems, John Updike, Knopf, 1960

What a wonderful counter to the claim that Science leads to a loss of wonder due to over-analysis (now replace ‘Science’ with ‘Science Education’ and that’s a different matter.)

Updike is referring to the fact that are about 50 trillion of these buggers passing through us every second! (rounded off to the nearest whole number, obviously).
I need to say more about these guys in a later post; their origins are just as amazing. Maybe I could use a podcast to try and get across the emotion that should be part and parcel of discussing neutrinos.

Anyway I say put that poem on the syllabus. And for the exam itself one word would suffice: “Discuss”.

 

Demonstrating how a tele works

Step One: Break the tele

Of course you could just shoot it

Then we looked at the working of the Cathode Ray Tube in a little more detail:
The cool thing about is that it enables us to look at the wave nature of the electron. Given that this (Quantum Theory) is one of the most popular areas of Science, you’d think that it would be on the actual syllabus.

“History repeats itself because no one was listening the first time.”

“That men do not learn very much from the lessons of history is the most important of all the lessons of history.”
Aldous Huxley

“If men could learn from history, what lessons it might teach us! But passion and party blind our eyes, and the light which experience gives us is a lantern on the stern which shines only on the waves behind.”
Samuel Taylor Coleridge

“What experience and history teach is this – that people and governments never have learned anything from history, or acted on principles deduced from it.”
G. W. F. Hegel

“Those who cannot learn from history are doomed to repeat it.”
George Santayana

“History repeats itself because no one was listening the first time.”
Anonymous

Taken from ageofthesage.org

The history of Easter Island is fascinating because it shows a civilisation slowly destroying its future in order to glorify the present. The people cut down their trees (which we now know were essential for their very survival) in order to carry stone for their famour statues, and must have continued to do this down to the last tree.
It would have make a nice moral story if the people had died off completely because they destroyed their key resource, but History is rarely this simple.
Nevertheless the moral still holds.

Watch The Mystery of Easter Island on youtube

The disappearance of the island’s trees seems to coincide with a decline of its civilization around the 17th and 18th century. Midden contents show a sudden drop in quantities of fish and bird bones as the islanders lost the means to construct fishing vessels and the birds lost their nesting sites. Soil erosion due to lack of trees is apparent in some places. Sediment samples document that up to half of the native plants had become extinct and that the vegetation of the island was drastically altered. Chickens and rats became leading items of diet and there are contested hints that cannibalism occurred, based on human remains associated with cooking sites, especially in caves.
From wikipedia