Ice floes in the Solway

I've never seen ice in the sea before. We went to Silloth yesterday, and, well, I have now. It is hard for the sea to freeze for 2 reasons:
1. Salt water needs to go down to -6 degrees C to freeze.
2. The sea has such a large thermal mass that it is hard for its temperature to change much. The work about specific heat capacity and latent heat is now at the end of the Upper Sixth but it is not difficult. It means that oceans always stay at roughly the same temperature, which is why coastal climates don't suffer from extremes.
This ice must have formed on the rivers up stream and be flowing out to sea, rather than being frozen brine. Famously, the same phenomenon took out the original Bowness railway viadeuct in the 1880s.

Lunar eclipse

Thanks to Mrs B for alerting me to this. I was up at 7 and freezing in the garden but it was worth it. It's got me thinking about the mechanics of this. To what extent does the Moon move into the Earth's shadow and to what extent does the Earth's shadow move onto the Moon? Whatever, it happens quickly over the space of less than an hour. Calculationa await.

My trip to Oxford

It snowed a lot on my trip to Oxford. So what do physics teachers do? Well, I measured the depth of the snow using my Barrow AFC ruler. Data is everytjing in physics. The final picture shows where the measurement was made outside Keble College chapel, which is opposite the particle physics building.

Ice

We went down to Keswick at the height of the big freeze the other week. If you look at the pictures, you can just see ice forming on Derwent Water. It is amazing that ice floats. It is the only example I can think of where a solid is less dense than the liquid from which it forms. This is because the bonds between the molecules rotate and spread as it solidifies. It is fortunate that this happens. If ice was more dense than water, lakes would freeze from the bottom up, killing all life. Life may never have survived on Earth.

The physics of reindeer

We went to visit the reindeer herd near Aviemore whilst on holiday. They were introduced in the 1950s as someone from Sweden recognised that the habitat was suitable. We have met the wandering herd of females on the Cairngorm plateau before. The males are kept in pasture most of the year so that the breeding programme can be managed to prevent in-breeding. Notice the size of the feet - large area to reduce the pressure on the snow. A bit of physics. Apparently their hairs are hollow - trapping air because trapped air is a marvellous indicator. Think about double glazing!

Black holes in Keswick

If you are down by the Theatre by the Lake in Keswick, put some change into the Rotary Club Wishing Well. It is constructed like a Black Hole. Coins spiral round and fall in. Once they are gone, they can't come back. Look at any picture of the field around a black hole on the Internet and you'll see what I mean.

Mrs B does an experiment at home

My wife did an awesome experiment and piece of analysis with the heating system at home last week. She ran the heating system all day - 7.30am to 8pm one day. The next day, she ran it for two short slots - 6.15am to 7.30am and then 4.30pm to 8pm.

Converting data into kWh, the all day use was 174kWh which cost £6.52.
The two shorter slots used 83.8kWh which cost £3.14.

So that suggests using shorter slots because it costs half the price.

But when you work out the cost per hour, running all day was 52p per hour but the two shorter slots were 66p per hour.

We need better insulation if we want the "keep it on all day" approach to reap benefits. The problem is clearly that the house cools down considerably between the two slots and then has to be reheated.

Pigeon Post

I've been reading the Arthur Ransome Swallows and Amazons series again for the first time in 35 years. In this book, they discover an ore in the hills that they think is gold. What I really like about this is that they are prepared to have a go at anything - an nearly get killed twice along the way - so don't try it at home! But they make pigeon post work, devising an automatic bell to alert them.
Then they work out how to make charcoal and build their own blast furnace. They try to test their ore using a mix of acids called aqua regia. I had to look this up! Try Wiki.

But it's their attitude, that if they hear about something they will try it. That's education.

The future of energy?

We went to Watchtree Nature Reserve on Sunday. You can see these turbines from the window of my lab. They are going round nicely this morning! Most opinions that I hear in these parts are against wind power and in favour of nuclear. It is very different to the opinions I heard in Nottingham. However, there are a lot of jobs in nuclear. Importantly, there is a meeting being held by Allerdale Borough Council in the Market Hall in Wigton on Thursday 25 November to discuss the council's interest in having nuclear waste buried beneath us. There will be presentations at 4.30pm and 6.30pm. I will definitely go to one of them. If you'd asked me 5 years ago I would have been strongly against nuclear power. In the mean time, I've read a book about the aftermath of Chernobyl which suggests it might not be that bad, so Ive got an open mind and will listen to what they have to say. It is my opinion that you can't be in favour of nuclear power but insist that all the bad stuff goes somewhere else. And of course you are allowed to disagree!

An interesting opinion on wind farms comes from a woman called Sara Maitland. She is a writer who has retreated to silence in a remote part of Galloway. Read what she says by going to her website, clicking on "About me" and scrolling to the bottom.

We notice wind farms, but can you spot the TV masts and pylons on this photograph of Skiddaw?

Jupiter

This awful photograph is my attempt to capture the planet Jupiter. I used a telescope that was actually designed for looking at wildlife, with a 40x lens. The beauty of a digital camera is that it will work in really low light levels because it has a quantum efficiency of over 70%. In other words, 70% of the light falling on its charge coupled device (CCD) is cpatured and recorded. The figure is 3% for old fashioned film, so a traditional camera won't take photographs through a telescope. You can tell that this is a planet and not a star because it forms a clear disc, not a point. In fact, I could see 4 of Jupiter's moons in a line stretching from the right of the planet. They have not come out in the photograph. I could even see light and dark bands on the surface of Jupiter. If you want to see Jupiter at the moment, it is the bright star in the south in early evening. So if you look from Wigton at 7pm, it will be the bright star above the Caldbeck masts. It was just such an observation that got Gallileo into trouble. He was the first person to see the moons of Jupiter. They change places over several days showing that they orbit Jupiter. In Gallileo's day, everything was supposed to orbit the Earth. Showing that moons orbitted another object seriously undermined the "Earth as the centre of the universe" theory.

My smart meter

I was bought a discount smart meter last year. It sits on my desk at home so that I can tell when Mrs B puts on the kettle in the kitchen! The kettle was on when the photograph was taken. Can you see how I know that? For me the most interesting thing has been to quantify the number of kWh used every day. In our house it is about 8 kWh at the moment so I suppose saying an average of 10 kWh might be a good ball park figure for attempting to answer questions like "how many kWh does Wigton use in a day?" I suspect that is an un-Googleable question so you'll have to fugure it out for yourself.

The Horizon programme

Hmm. The previous post didn't publish and stayed as a draft, so none of you will have been able to read it. Hope you had a good Powers of 10 day - do watch that 10 minute film from the web link.

Monday's Horizon documentary about what happened before the Big Bang is very good.
http://www.bbc.co.uk/iplayer/episode/b00vdkmj/Horizon_20102011_What_Happened_Before_the_Big_Bang/

I thought that the most useful bits were at the end when they bothered to get away from the maths based theorising and actually talked about finding experimental evidence to back up the claims.

Various things

Can I remind you to celebrate world Powers of 10 Day on Sunday?

http://www.powersof10.com/



Also next Tuesday 9pm BBC2 there is a Horizon documentary about what happened before the Big Bang. The idea is that there was a multi-verse and our Universe happens to be one of squillions out there. This means that the statistical fluke that brought life would have to happen so eliminating the need for God to start the Universe. You get rid of God by invoking squillions of Universes that we can't touch. Make your own mind up - see what evidence they give.



Yesterday 12 Nobel Prize winners wrote to The Times to protest against the immigration cap because it would have stopped the UK winning a lot of Nobel Prizes, including this year's Nobel Physics Prize.

Pink moon

I took this picture earlier in the summer. When the the moon is low down in the sky, the light from the moon comes through the atmosphere at an oblique angle. This means that it travels a longer distance through the air than if it had hit straight on. The light hits tiny particles in the air it is scattered. The short wavelength colours at the blue end of the spectrum are scattered first leaving the redder colours to reach us. Hence the moon looks pink. Incidentally, they say that the moon looks bigger when it is nearer the horizon but that this is an optical illusion.

The future of physics in the UK

The Institute of Physics is concerned that physics needs adequate funding in this climate of cuts. I do believe that physics is vital for the future of the country. People who have studied physics will be responsible for providing energy and for the innovative technology that can earn the country billions. Being very careful not to make this column party political, I wanted to comment on what I heard on the business news on Radio 4 this morning. A representative of the business community was saying that the cap on non-EU nationals being allowed to work in the UK was having a big effect. I woke up when she mentioned the energy provider EDF. This is the reason: As physics has been allowed to run down as a subject in this country, we have begun to rely on hiring physicists from abroad. At the moment, strong nations for training physics are Russia, China and Japan. They would be affected by the cap. From my point of view I think the country needs to decide one of two ways:
1. Do we give up on physics because no one here is interested and just hire physicists from the east?
2. Do we decide that hiring from abroad is a bd thing but then work hard to boost physics in this country?
Answers on a postcard... However, I need to make time to write to my MP to air these concerns.

Lightning conductor on Cockermouth church

This week's Lower Sixth homework asks students to estimate the resistance of the lightning conductor on Wigton church. Here's the one at Cockermouth. If you enlarge the first picture you can see it snaking up the right hand side of the tower. The second view, from the bottom of the tower, shows how it then heads down to disappear into the Earth. To estimate the resistance, we need the dimensions of the conducting strip. So how wide and deep do you think it is? And looking at the spire, how many metres tall would you say that the building is? Good estimation skills are important in physics and engineering. I usually start by imagining how many people stacked on top of each other would reach the top, and work to an over-estimate that the people are two metres tall...

Physics on the TV and radio

Give the X-Factor a miss this week. Saturday night is physics night!

Channel 4: 8pm. Stephen Hawking has an hour on his theories of the universe.

However, if you are feeling very grown up, you could listen to Radio 4. Same time (8pm) they are doing an hour on Richard Feynman. He's my favourite physicist - a genius but also deeply unconventional. Hopefully they'll have some stories about his often bonkers life. But you could catch this on the i-player later...

I'm not the only one

Hopefully, if you click on the picture you should be able to read the letter entitled "There's a fault with power and the story". It's from The Cumberland News letter page this August. The journalists used the wrong units for power and energy. Tsk! Tsk!

A trip to ring the bells at Cockermouth

In the holidays I went down to ring the bells for a wedding in Cockermouth. This grave stone was outside the door to the bell tower. It turns out that Rev Fearon Fallows who died in 1831 was the "Astronomer Royal to His Britannic Majesty at the Cape of Good Hope". He was also a Fellow of St John's College Cambridge and FRS. FRS means "Fellow of the Royal Society" and is an honour awarded to the very top scientists in the UK. Our own Harry Elliot was FRS. So this was the grave of a distinguished physicist by the look of it, confirmation that we do live in a great area for physics. The top of the grave stone has an interesting early map of the world. I've also added some views most of you won't have seen of Cockermouth from the roof of the church beside the bell tower.

A trip to the south

We went on a tour of the south last week. It involved passing through the Watford Gap services on the M1. These have huge cultural siginificance because they are said to be the place where the south starts. They are actually nowhere near Watford, being just north of Northampton. The north/south thing is a bit odd here in Wigton, where almost everywhere in England is south of us.

We were struck by the amount of traffic and general busy-ness in the south. There is a constant hum of traffic noise in many places. These photos were taken at 11am on a Monday morning. Look at the difference in the people heading north (towards us in the second photo) and south. I stood on the bridge and counted 40 cars going north in 1 minute. That's probably about 3000 people an hour moving at what is not a particularly busy time in that direction...

Sundial

I went to Amble in Northumberland. Next to the harbour is this large modern sundial. The notice explaining sundials is very interesting. It explains why a sundial doesn't show perfect clock time. Part of that follows on from my previous post which noted that true sun-highest-in-the-sky midday is different in Wigton compared to London. This display panel also explains that the height of the sun in the sky (time of year) has an effect too. Click on the picture to enlarge it.

Climate change on Panorama

Last week's Panorama programme on BBC1 was about the science of climate change. Now Panorama is a far more tabloid style programme than was the case when I used to watch it 30 years ago. However, I was interested that the supposedly disagreeing scientists all seemed to beleive that the world is warming. The only people who didn't believe in global warming were members of the public. Small sample size, for sure, but interesting none the less. The controversy amongst the scientists seemed to be the validity of the "hockey stick" global temperature graph.

Anthorn aerials

If you look carefully into the sunset in the pictures of the previous post, you can make out the aerials at Anthorn, 10 miles north of Wigton. They now have the Greenwich Time Signal. This takes some thinking about. Noon should technically be defined as the time at which the Sun is highest in the sky. This varies from place to place even within England. So noon in Carlisle is 8 minutes later than in London if done this way. Before the industrial revolution, this is exactly how they set the time on the big tower clocks in each time. Then they invented the train which ran to timetables. If each town had its own locally set time, the timetables wouldn't work so it was decided to standardise the UK so that all clocks said 12noon when the Sun was highest over Greenwich in London, because that's where the official observatory and naval headquarters were. A signal was sent out to all towns to synchronise the clocks. This type of time is called Greenwich Mean Time (G.M.T.) Until recently, the signal was sent out by radio waves from big aerials next to the M1 at Rugby. Now we've got the honour of broadcasting the nation's time!

Summer solstice

It was the longest day of the year yesterday. From our house, the Sun sets well to the north west. That's the payback we get in the north for the very early sunsets in mid winter. Watching the Sun touch the horizon and then visibly go beyond the horizon is about the only way I know of experiencing the turning of the Earth. If you enlarge the first picture you can see Anthorn aerials. More on them in a future post. In the second picture, the hill to the right of the telegraph pole is called Queensbury. It is nearly 40 miles away across the Solway in Scotland.

James Lovelock

I have been reading this book. James Lovelock's Gaia Hypothesis has been one of the more controversial theories in recent years. He claims that the whole Earth acts as a living organism and regulates the conditions on the planet to ensure the continuance of life. I still find it hard to accept in full but there is now irrefutable evidence that living organisms do have a sizable effect on the atmosphere and thus affect the living conditions. I changed my mind on Lovelock after watching a BBC4 profile of him. He invented the detector that enabled the hole in the ozone layer to be found. He clearly believes in science done by making observations. This is important.

Campaign for mass

Further to my post last autumn about the Campaign for Mass, imagine my horror when my wife pointed this shocker out to me over the breakfast table. Any fool knows that if it is measured in grams it must be mass. Perhaps they could state the weight of the cereal as 4.5Newtons...

Cyclopedean rock formations

The Cairngorm Mountains are made of granite. This is an intrusive igneous rock that solidifies over millions of years underground, the magma having never made it to the surface. Then over the millenia, the rock layers above wear away. What happens is that the release of the pressure that the rock was feeling when it was formed causes it to expand. The expansion causes it to split vertically and horizontally. This means that many granite rock formations look like they are made out of regular blocks. Some people used to think they were built by an ancient civilisation of giants. The name "Cyclopedean" comes from the giant Cyclops in Greek mythology. I have actually only ever heard it applied to the mountains on Arran. The prominent lumps of hard rock left exposed on the horizon are called TORS in Devon. You can see them clearly along the horizon in the picture of Beinn Mheadhoin. If you can't pronounce the Gaelic, go to http://www.munromagic.com/MountainInfo.cfm/13. If you click the loudspeaker, it will say it for you.

Cairngorm weather station

The top of Cairngorm mountain, the sixth highest on these islands, turns out to have a weather station feeding data to Heriot-Watt University weather station in Edinburgh. Now I need to look up the data!

The Curious Incident again

Last December I wrote a bit about the book "The Curious Incident of the Dog in the Night-time" by Mark Haddon. It is written from the point of view of a boy with Asperger's Syndrome. He sees things from a very different point of view. I like his views on time. He explains why he needs to have timetables, so that he knows exactly what is going to happen and when it is going to happen. Not knowing scares him. He says:
"Because time is not like space. And when you put something down somewhere, ... you can have a map in your head to tell you where you left it.....And a timetable is a map of time, except that if you don't have a timetable time is not there like the landing and the garden and the route to school. Because time is only the relationship between the way different things change, like the earth around the sun ... and it is like west or nor nor-east which won't exist when the earth stops existing and falls into the sun because it is only a relationship between the North Pole and the South Pole.."
I think this is very profound physics. This is dedicted to those who write that "time slows down" when a crumple zone crushes up in a crash!

Lightning conductors

One of the great things about being a bell ringer is that I get to up the church tower. You get the best view of Wigton from the top. Notice the thick metal strip running down from the spike at the top. It's a lightning conductor. It goes all the way down the outside of the tower and is then concreted into the ground. The idea is twofold:
1. If lightning does strike, the massive current is carried down the metal, which has a much lower resistance than the masonry. This stops the masonry overheating and the mortar being broken.
2. It actually deters lightning. If the cloud has a large positive charge, it attracts electrons, which are negative, up from the ground to the tip of the spike. The large concentrated charge ionises the air molecules and then repels negative ions up to the positive charge. This neutralises some of the charge, making lightning less likely.

Basalt dykes

This photograph is of an igneous dyke on Anglesey. Molten magma must have forced its way sideways between existing layers and then solidified. The way that molten magma moves under the surface of the Earth is very much to do with physics. It is due to convection cycles in the mantle. I was interested to note that in Brian Cox's series on the Solar System, he attributed the loss of atmosphere on Mars to the cooling and solidifying of its molten core.

Wavefronts on Anglesey

Looking out over the sea from South Stack near Holyhead on Anglesey, I was able to see waves being reflected. Looking down, you see the ripple pattern of the peaks of the waves. This is called the wave front. I have drawn them on in black in case you can't pick them out. Huygens favoured the wave front analysis. Isaac Newton prefered to draw rays which show the direction of motion. You can't see motion in a still photograph so I've had to draw them in for you as arrows. Now you can see that plane waves (flat ones) are coming down from the top of the object and reflecting from a circular promontary. If plane waves reflect from a curved object, the reflected wave fronts are curved too.

Wrong again!

The blue sky is definitely polarised but not because of the ash cloud. The blue colour is caused by scattering. You can look at the post about this on this blog last September. The scattering process polarises light. That explains a thing that I noticed - the polarised light was in every direction excpet that close to the Sun. Light close to the Sun is less scattered.
Also, I was surprised by how quickly Mercury disappeared. I was confidently telling a group on Friday night that it was just behind a cloud, but it clearly wasn't. It must have moved a long way across the sky in a week and have changed to a position that is below the horizon. Mercury was the speedy messenger of the gods in mythology. That's why the fast planet got its name. Now I have seen it for myself.

Ash cloud and polarised sunlight

I heard a suggestion that the ash cloud from the Icelandic volcano might polarise sunlight. Ordinarily, light waves from the sun are unpolarised. This means that some vibrate up and down, some vibrate side to side and others vibrate diagonally. If the ash cloud polarises the light, it would mean that it would vibrate in one direction only. You can check this with a polarising filter. Point it at the sky and rotate it. If it goes alternately light, dark, light, dark every quarter of a turn then the light is polarised. I've just been out to try it and this has turned out to be the case. Of course, I need to try again when the ash cloud has gone to be fair. You could try it if your sunglasses are polarising - some are and others are just thick filters.

Planets in the night sky

I watched The Sky At Night on BBC4 last week. It's almost the longest running programme on TV and is, shall we say, a bit dry. However, they explained where to look for 4 planets that are visible before 10pm at the moment. I went looking. At 9pm, look in the direction of the sunset. There is a really bright star. That's actually the panet Venus. Down and right of it, maybe about the width of your hand held at arm's length, there is a much fainter dot. That is the planet Mercury. I'd never seen Mercury before. Last night I picked it out from the car park in the middle of Wigton. Mercury is closest to the Sun so it is only visible in the half light at sunset (and just before sunrise at other times). This makes it hard to see because it is not very bright. It is also close to the horizon as well and it has gone before it is properly dark. All this makes it hard to see. So I photographed Venus. It is clearly a disk and not a point. That makes it a planet. My next ambition is to see Venus go through phases like the Moon (Eg full disk, half disk, quarter disk etc) Galileo observed this. My telesope is really for wildlife not stars, but last night I picked out the rings of Saturn with the 40x lens. Life doesn't get much better than that! By the way, Saturn is roughly South West at 10pm and about 30 degrees up. Mars is almost above your head and clearly redder. You have a day to watch the second of the two programmes which tells you where to see the planets if you whizz through to nearer the end. http://www.bbc.co.uk/programmes/b006mk7h

Double rainbows

We had a very wet holiday on Anglesey over Easter but I did manage to catch up with a double rainbow. I read about these years ago but pulled up short a year or so ago when I finally noticed that the colours are reversed on the outer rainbow. Enlarge this picture and take a good look at it.
The colours of a rainbow are caused by total internal reflection of the light in a raindrop and the subsequent refraction as it leaves the front of the drop. For a double rainbow, the light reflects twice on the inside before exiting.
See http://en.wikipedia.org/wiki/Rainbow

Miles per litre

I'm impressed that many of my classes seem to know the fuel economy of a car in miles per gallon. Problem is that petrol is sold in litres now. As part of my quest to verify the data in David MacKay's book last summer, I started noting the amount of fuel that went into the car and the mileage. Over 5 weeks of the summer holiday, our car averaged about 17 miles per litre. Looking in the handbook, that comes between the given values for motorways and for city driving, so it sounds about right. They test their cars on rollers in a lab so I'd like to know if they factor in air resistance as well.

Join the Institute of Physics

If you are studying physics in the Sixth Form, you can join the Institute of Physics for FREE. This would look good on a UCAS form but is also a good thing in its own right. I trained as an engineer but it is through my membership of the Institute that I have come to think of myself as a physicist. They send me the monthly magazine that I put up in the lab. You would be able to access this online.
The Institute is the organisation that promotes and regulates physics in this country.
www.iop.org/16-19 to sign up!

Orbital resonance and metallic hydrogen

I've always found the planets a bit boring because they just seemed like a set of odd facts that needed explaining. A bit like the classification of animals. But Brian Cox's TV programmes are sucking me in.
Having been asked by year 10, I have been reading up on Jupiter. Can you stand on the planet? I'd never really stopped to think about its "gas giant" status. It's not all as simple as gas apparently. Although mainly hygrogen and helium (the colours are traces of other gases), the intense pressure towards its core turns the hydrogen into "metallic hydrogen". I'm just getting to grips with what this is. I'm assuming it must conduct due to delocalised electrons to earn its name. Look it up on the Internet
On last week's programme, Brian Cox looked at the rings of Saturn. Apparently a larger outer moon does one orbit in the time it takes a smaller object within the rings to do two orbits. This means that once every two circuits, the inner object gets an extra gravitational kick. By going faster it moves to a different orbit, thus leaving a clear track within the rings.

Is everything we know about the universe wrong?

I missed this programme on Tuesday night so I'm watching it on the i-player. I know about dark matter and dark energy, but I've never heard about dark flow. I'm trying to learn something new about physics every day, so hopefully I'll know about dark flow by the end of the day.
http://www.bbc.co.uk/iplayer/episode/b00rgg31/Horizon_20092010_Is_Everything_We_Know_About_The_Universe_Wrong/

Brian Cox on BBC2 on Sunday night

If you missed the programme last night, you must see Prof Brian Cox on the wonders of the solar system:
http://www.bbc.co.uk/iplayer/episode/b00rf172/Wonders_of_the_Solar_System_Empire_of_the_Sun/

He covers a lot of stuff about the Sun and the Solar System. I love his enthusiasm. I am going to re-create Herschel's tin can experiment in the summer and I particularly admired the "That's why I love physics" aside at the end of that sequence in the programme.
If it doesn't make you want to become an astronomer, nothing will.

Mist in the valleys

Sorry there haven't been many posts recently. It's the busiest time of year! Still no sunspots, by the way. That's 5 months I've been watching.

At half term, I was up in the hills above Haweswater. There was a reasonably cloud base above our heads but mist kept forming in the valley below and then rising up past us. see photo.

Here's the physics explanation that I came to:

The slopes below us were south facing and catching the warm sun.

This made the snow melt and then evaporate.

The water vapour hit the cold valley air and condensed into mist.

This was warmed by the Sun so it expanded and became less dense, thus rising.