Physics Stop

Featured image: The Beirut explosion shockwave

The Beirut explosion shockwave

Marcus Wilson • Aug 06, 2020

That was clearly a huge explosion. Just after the explosion, we see a cloud of ‘fog’ moving outwards at high speed. This is a shockwave, rather similar to that which causes a sonic boom. The ‘fog’ is caused by water condensing from the atmosphere in areas of intense low pressure and temperature, and parallels the sonic boom cloud, or … Read More

Featured image: All-pervading Waikato dampness

All-pervading Waikato dampness

Marcus Wilson • Jul 17, 2020

Yesterday we arrived back in Cambridge after a few days holiday in Auckland, being tourists. We sampled such delights as the unheated hotel swimming pool,  the complicated and expensive process of getting on a bus (basically having to find somewhere from which to buy a HOP card, for a non-refundable $10 a card), the completely non-social distanced pedestrian rugby scrum … Read More

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Featured image: Pass the pigs – ad (almost) infinitum

Pass the pigs – ad (almost) infinitum

Marcus Wilson • Apr 20, 2020

I warn you, this post will make little sense to anyone who doesn’t know the game Pass the Pigs. What do you do on a damp Easter Holiday Monday? (Not that the Holiday Monday bit makes much difference in our house…) Play Pass the Pigs of course. And what do you do when you’re a physicist who’s finished playing … Read More

Featured image: Expanding houses

Expanding houses

Marcus Wilson • Apr 08, 2020

It’s  a beautiful autumn afternoon, we need to get out of the house, and so our bubble sets off on a bike ride around our local neighbourhood, Cambridge Park. The bikes come out of the garage, and, being really certain we have a front door key, close the garage door again. And off we go. A while later, having been … Read More

Featured image: Delays in feedback: Learning to drive, brain waves and COVID-19

Delays in feedback: Learning to drive, brain waves and COVID-19

Marcus Wilson • Mar 11, 2020

With the numbers of new COVID-19 cases in China diminishing by the day, China now faces a problem. How to get the country back to work, or partly back to work, or more back to work, without taking too many risks with the virus taking off again. The risk can’t be eliminated, except by shutting its borders altogether and eliminating … Read More

Featured image: A beginning of semester corona-rant

A beginning of semester corona-rant

Marcus Wilson • Mar 04, 2020

I’ve had enough of COVID-19 now. No, I haven’t had it (well, not that I’m aware of), what I mean is I’ve had enough of reading misleading headlines, hearing xenophobic attitudes and dealing with outright selfish behaviour. Let me elaborate: Point 1 We know that every outbreak will be accompanied by a kind of tsunami of information, but also within … Read More

Featured image: Mucky rain

Mucky rain

Marcus Wilson • Feb 20, 2020

While the south of New Zealand has been struggling with too much rain in recent days, here in the north we are so very short of it (though Saturday’s forecast looks promising).  Basically, we have had almost none since Christmas. As someone who relies on rain to wash the car, this means my car is now looking rather mucky. Read More

Featured image: The numbers are the numbers, except when they’re not.

The numbers are the numbers, except when they’re not.

Marcus Wilson • Feb 14, 2020

I’m not quite sure of what to make of the new figures for COVID-19 (as we must now call the novel coronavirus – though I’m not sure the capitalisation is correct) from Hubei province: Image from https://www.bbc.com/news/world-51495484  The spike yesterday is a consequence of a using a different way of defining a case – one based on a clinical diagnosis (i.e. Read More