Tagged: heat

Heat transfer within edible objects - Physics Stop

Marcus Wilson Mar 08, 2010

The veggie-juicer in our kitchen will happily take fruit, such as apples and oranges. Apparently, in the case of the orange, it works best if the fruit is cold (but not frozen) throughout. So here's the question my wife asked me last week: If I have an orange at room temperature, and want to cool it to fridge temperature … Read More

Heads I win, tails you lose - Physics Stop

Marcus Wilson Jan 25, 2010

The comment on my previous entry raises a few  issues with the way we feel heat.  (NB for those who normally read this blog on http://www.sciblogs.co.nz , you'll need to go onto physicsstop to see the comment - http://sci.waikato.ac.nz/physicsstop ) How hot we feel has more to do than just what the temperature is.  Anyone who has stood … Read More

Can you feel the cold? - Physics Stop

Marcus Wilson Jan 21, 2010

Writing the last piece about fridges has reminded me about a comment I heard from a fellow student while I was an undergraduate. I can't remember the exact circumstances, but it quite possibly had something to do with objects in liquid nitrogen.  Anyway, the comment was something along the lines of 'The temperature's so low you can feel the cold radiating … Read More

BBQ Physics - Physics Stop

Marcus Wilson Jan 19, 2010

Here's another little bit of physics seen in everyday stuff.  When disconnecting the gas cylinder to our camp stove while on holiday, I got a bit of a shock at how cold it was.  It shouldn't have shocked me - that's how it should be. When gas is made to expand it cools down. And in the gas cylinder, compressed gas is … Read More

Ice and the freezer - Physics Stop

Marcus Wilson Jan 11, 2010

Last Saturday I got around to doing one of those long overdue jobs in the house - defrosting and clearing out the freezer. There are numerous reasons why this was a good idea - it's not just about getting rid of the food that has been there rather too long, but also about making sure it works properly. There was probably about … Read More

Back to the long-neglected blog - Physics Stop

Marcus Wilson Jan 05, 2010

Well, I'm back in at work now after three weeks and four and a half thousand kilometres.  Pleased to discover that in my absence the house hadn't burnt down, there had been no floods and Christmas presents hadn't been stolen.So it's now back to trawling through three weeks' worth of emails, catching up with how student projects have developed in … Read More

Simple Machines - Physics Stop

Marcus Wilson Dec 26, 2009

There's a lot to do while driving.   Look at the road - watch the speedo (98 kmh - OK there), watch the road - look in mirrors - check fuel gauge (half - OK there) - watch road - watch that car at the intersection ahead - check temperature gauge (where it should be) - eyes on road - glance … Read More

Climate change - Physics Stop

Marcus Wilson Dec 10, 2009

I feel that, as a physicist, I should be making some reasonable and informed comment on the Copenhagen summit. After all, climate is immensely physicsy. We have fluid flow, conduction, convection and radiation of heat, interaction of electromagnetic radiation with electrons in molecules, scattering of light by small particles, solar activity (on second thoughts, … Read More

Beyond cornflakes - Physics Stop

Marcus Wilson Nov 02, 2009

This is something that Aimee Whitcroft at the Science Media Centre in Wellington drew my attention to - thanks Aimee.Most of us who have ever eaten breakfast cereal will probably be familiar with the phenomenon whereby the larger flakes of whatever-your-favourite-breakfast-is tend to be at the top of the packet, whereas the smaller flakes tend to accumulate at … Read More

Climate engineering - Physics Stop

Marcus Wilson Sep 28, 2009

So PhysicsWorld has done a nice article on some of the 'engineering' solutions that might be available for tackling global warming.Generally they are pretty ambitious global-scale plans to turn down the thermostat a bit, given the premise that either carbon dioxide emissions will not fall sufficiently or that, even if they did, the earth would still be too hot and something else … Read More