Monday, July 6, 2015

Physics teaching again

So I'm teaching a physics unit with around 20 students in it.  And I'm pleased to say that I think they are starting to discuss problems with each other when I ask them to.  Not sure why they don't like doing this, but they are starting now.

Discussions are great.  You say what you think, and others explain why you are wrong.  You adjust the mental model that you have, and your understanding improves.  Students don't seem to like them - preferring to defer to the expertise of the lecturer.  But its not the best way to learn.  The lecturer has long forgotten what it was like to be learning this stuff.  Their fellow students know exactly what it is like.  They are the ones to help.

Sunday, July 5, 2015

Rain and punctures

I cycle a lot.  270km the week just gone.  Consequently I hate rain and punctures.

Friday I got a puncture - first in a few months.  So I was late to breakfast with Nick, Mark & Carlo.  Ted would have been there, but he slept in.  So I fix the puncture that night, but the glue seems dodgy, and the patches are old and also seem a bit dodgy.  But anyway, in the end it seems to have taken.

Saturday I ride, and it rains, and I get wet.  But it serves one purpose - I finally clean my bike.  Not properly, but superficially.

Sunday morning, I ride and join some others.  Gags gets a flat.  I tell him I'd give him my spare tube, but its a bit dodgy, so Liam patches his tube.  Roland rides past - he's late because he's had a puncture.   Riding home, rain threatens.  We pass someone fixing a puncture.  Paul is going to meet us at Canning Bridge, but texts saying he has a puncture, and we should go on without him.  I do a short extra loop with Ron and once thats done we bump into Paul walking his bike.  He's had another puncture.  I give him my dodgy tube, and it holds up ok.  As we are changing it, a guy walks his bike past - he's had 3 punctures and has been abandoned by his mates.  A group ride past - they've had 3 punctures between them that morning.  I get home before the rain.

I shower and set off in the car to pick up Cam.  The car struggles up Greenmount Hill as usual.  Then once its over the top of the hill, it dies.  Engine light comes on and car stops dead.  I ring Cam.  I ring the RAC and organise for breakdown assistance.  I try starting the car, and it turns over but doesn't fire.  I try again after a while, and it fires, but immediately dies again.  A few minutes later, it starts just fine and drives just fine.  So I pick up Cam.  On the way home the rain sets in.  How will I get to the footy?  Freo play Brisbane at 2:40pm.

Back home and it keeps raining.  I decide to wait for it to stop and ride to the footy.  So I set off with rain threatening and when I'm half way there, I get a puncture.  The front tyre goes flat in about 3 seconds.  So I pull off the cycle path and remember I'm going to have to patch the tube with dodgy glue and patches because Paul has my spare tube.  As I get started, so does the rain.  I move into the shelter at the front of a dodgy cheap hotel that smells of stale cigarettes.  I'm getting pissed off.  I pull out the tube and try pumping it up to find the leak.  It doesn't hold air at all.  I try looking at it closely, but my glasses fog up.  I can't see anything wrong with the tube.  I start weighing up my options - lock the bike up and walk home bare foot?  Take a taxi?  Anyway, after a while I start squeezing small sections of the tube until I hit the jackpot and felt a bit of air on my face when I squeezed.  There was a small split in the tube.  I patch it, and pump up the tube without much hope.  But it seems to hold air.

I set off for the footy again.  Get there dry with no problem.  Its half time, and Freo and Brisbane are tied 5.2 apiece.   The rain has stopped. The third quarter is very tight.  But finally in the 4th Freo kick away and have an easy win.  I see Paul & Katya, and have a chat with Karen and Mick after the game.  The ride home is fine - except the battery for my front light is nearly flat - so I just turn it on when I reckon its needed.

I've never seen a day with so many punctures.

Saturday, July 4, 2015

Those cheap tabloid gotcha moments again

The very serious editor at large of the Australian, Paul Kelly, was on Q&A when he referred to a question in the previous Q&A as a cheap tabloid gotcha moment.  The question was from Zaky Mallah, a slightly nutty sometime supporter of the Free Syrian Army, and it was directed to a government minister, Steven Ciobo.

So what is a cheap tabloid gotcha moment?  Well, its when the shonky repairman is confronted with the victim of his dodgy work, photos and a competent tradesman of some repute.  All of a sudden his version of events collapses.  The tissue of lies he's put together is torn to pieces.

Note that this relies on something.  It relies on the position of the shonky repairman being indefensible.  And that is why the Mallah/Ciobo interaction was not a tabloid stunt.  Ciobo is putting the government position on legislation it is introducing.  Legislation that will have been carefully prepared and scrutinised.  It should be defensible.  Mallah asking, "What would have happened in my case if this legislation was in place at the time?" is a legitimate question that should have a solid answer.

Having said that, it can be tricky.  Say you are asked a subtle question about Newtonian mechanics.  Now I reckon most competent physics educators could answer that.  If the questioner thought they had a "gotcha", you should be able to answer it, pointing out clearly why it is not a "gotcha", and maybe putting it into a broader context so that it becomes obvious how it works.  Now even if you understand the physics pretty well, you might get caught out by a "gotcha" - but not if, like Ciobo, your job is to have your head around this stuff, and be able to defend it.

But it really is not that easy.  What about special relativity?  There are plenty of tricky questions in special relativity, and I defy anyone to answer some of these to the satisfaction of the asker.  There is just too much thinking behind it.  You can't make the answer easy.  You can't easily reduce every question to its core misunderstanding - even when you know what it is.  It just takes more time than is available to do it properly.  And even competent physicists sometimes remember key results without remembering how they were derived.  They knew it once, and satisfied themselves that it was valid - but its not at their fingertips.  And in the end, the questioner will have to be satisfied that you believe it to be true, and will point them in the direction of a good book or web site if they need convincing.

The take away message, however, is that Steven Ciobo is a bully and a dickhead.

Monday, June 29, 2015

Paul Kelly of The Australian is a total nong

Watching Paul Kelly on Q&A.  What a nong.  He shows no insight whatsoever.

He objected to the presence of Zaki Mallah on Q&A last week because he thought having Mallah ask the minister a question was a cheap "gotcha" moment.

Now, while it is often quite easy to answer vague questions of principle, it is not so easy to confront a specific question from someone who through their own experience will be able to pull you up if you drift off point.  If you are confident in your principles, you can answer the question.  You can do so in a way that will demonstrate to people that you, at the very least, have a self consistent framework, and at the best show why they should support you.

Zaki Mallah's question was a "gotcha" moment.  It worked because the stupid minister had no useful response.  It worked because the current government is stirring up fear over terrorism, and there is precious little substance behind it.

And Paul Kelly repeatedly fails to understand this.  One might even suggest that his failure to get this point was, perhaps, deliberate.

Actually, just watch Q&A.  Paul Kelly really is a pompous shit.  Lawrence Krauss is great.  The woman who isn't Tanya Plibersek is also great.  Tanya Plibersek is good.  Tim Wilson is a fool.

Buddy - 1 week. WTF?

Look, if Buddy gets 1 week for that, can there be any doubt that the AFL has a bias towards Sydney?

I've got nothing against Buddy.  Wish he played for Freo.  But when you run past the ball, size up your opponent coming the other way, and your eyes light up saying "bewdy, he doesn't know I'm here, I can knock the shit out of him!", and then you knock the shit out of him, including that bit above the shoulders, commonly known as the head, then maybe, just maybe, you should get a 3 week holiday.

But he got 1 week.  So the AFL is corrupt.

Here's Buddy's one week hit.

And here is Fyfe's that got him a two week suspension.

And here is Ballantynes that got him two weeks.

Anyway,  the pro-Sydney bias is pathetic.

Friday, June 26, 2015

Superannuation rule changes

Well, you could say its my fault.  Having gone off anti-depressants I find myself getting angry more easily.  But its not all my fault.  Watching the dickheads in the Liberal Government isn't helping.

Take superannuation.  In Australia we have had superannuation for a long time.  Back in around 1990 compulsory employer superannuation contributions were introduced.  And when this happened, not-for-profit industry super funds were set up with representation from unions and employers.

The important thing to note is that the industry super funds outperform the for-profit super funds run by the big banks and insurers.  Its hardly surprising.  If you want to make a profit, you won't have as much money left for your members.

But the government, in their never ending, mind boggling assault on common sense has decided that industry super funds must have one third of their board members "independent".  Now being a board member is just the sort of thing that the mates of Liberal politicians do for a living.  They go to business lunches and make important decisions about other peoples money.  Some of these people are financial advisors, which roughly speaking means they take some of your money for investing in a way that is no better than you could do yourself, if you could be bothered.

One of the first, and successful, moves by this government was to make sure that financial advisors could keep taking bits of your money long after they had given you any advice.  You know, the previous government legislated that if anyone was taking your money on an ongoing basis, that they had to contact you every couple of years and see if you were ok with it.  Clearly financial spivs can't survive this extremely high level of customer contact.  So their mates in government rolled it back.

And now this bunch of thugs want to open up industry super boards to their thieving mates.  I'm angry, and its not just going off anti-depressants.

Wednesday, June 24, 2015

Friends of Steves

Time to start telling stories of the past.  And this one is about FOS - the Friends of Steves, a shadowy criminal organisation of the 1980's.

Once upon a time in the leafy suburb of Nedlands was a pub called Steves.  If you went to uni, you went to Steves.  At least thats how it was in the 70's.  One of my favourite memories is of going to Steves with some of our physics lecturers at the end of 3rd year uni.  I got pretty drunk and road home along Mounts Bay Road, trying very hard to stay close to the kerb as the cars whizzed past.  In those days there was no cycle path, so you diced with death on the road.  At one point I clipped the kerb and fell off the bike.  I was drunk.  I remember being embarrassed, and then hopping back on the bike and riding home.  What else could I do?

Anyway, as we got older, Steves became a regular haunt.  Thursday night was great, with a band called Boogy Street belting out great covers, including Brown Eyed Girl.  Loved them.  But the Sunday session was the key thing at Steves.  You see, Perth had strange drinking laws back then, and pubs could only open for certain hours on a Sunday.  And Steves opened from 4:30pm to 7:30pm.  So you knew, that if you wanted to catch up with friends, all you had to do was rock up to Steves on Sunday arvo.  Come straight from the beach, still wearing your bathers.  Everyone was there.  Everyone drank too much (this was before we took drink driving so seriously).  It was the place to be seen.  Steves was a big place.  You could fit hundreds of people there.  You had to park hundreds of metres away.

The locals did not approve of Steves.  The newspapers were full of stories of people urinating, defecating and fornicating in the front yards of houses near Steves.  Urinating?  Well yes, there was a lot of that.  But I never saw any defecating or fornicating, but it may have happened.  Anyway, the tide was turning against Steves, and the local council decided to impose parking restrictions.  To be precise, no parking on Thursday night or Sunday afternoon anywhere within about a km of Steves.  And having decided this, they duly implemented it with a whole lot of parking signs going up.

My memories of this are a bit vague, but I seem to remember FOS being formed at a house we rented in Richmond Street in Leederville.  This would put the date at around 1989.  FOS consisted of two intrepid individuals, who I will call "Ted" and "Mark", to protect their identities.  For all I know, FOS could retrospectively be classified as a terrorist organisation, and its members deported.  You can't be too careful.

Anyway, having formed, FOS got straight to work.  Dressed in dark clothes and mounted on bicycles, they set off for Nedlands.  I imagine it was late at night, and I reckon there was no moon.  So "Ted" and "Mark" cycled around Nedlands, locating the anti-Steves parking signs.  And when they found one, they uprooted it.  They dumped them in the river.  They hid them in gardens.  They made sure that there was no trace of those signs.  It must have taken hours, but FOS were no shirkers, and they didn't quit until every sign was gone.  They were not lazy like the yoof of today.

So that Thursday, and that Sunday, people parked exactly as they had done for the previous 20 or so years.  FOS had won.

Unfortunately, the council fought back.  They made new signs and put them back up.  And courageous as the Friends of Steves were, they were also not fucking stupid.  This time the signs stayed up, and gradually over the next few years Steves died down.  Now its a bottle shop, cafe and restaurant.  And a lot of very, very expensive apartments.  The pub culture of the 70's and 80's is long gone.  Back in the early days, I'd go to see Dave Warner play at the Shents.  I'd go without shoes or thongs, on a Saturday night, and they'd let me in.  We'd stand on the tables.  It was grouse.  Now the Shents is old peoples homes.