Saturday, February 15, 2020


Google is complaining about blog layout. Changing to a current theme...

Wednesday, February 27, 2019

This blog

Posting each month is becoming difficult. Posts will be done in a less regular way from now on  :)
(I doubt anyone will notice...)

Tuesday, January 29, 2019

The north pole of the Earth is moving

We teach about the magnetic pole of the earth as if it were fixed but in fact it moves. And recently it has started moving faster for reasons we do not quite understand...
According to recent research reported in Nature:
Something strange is going on at the top of the world. Earth’s north magnetic pole has been skittering away from Canada and towards Siberia, driven by liquid iron sloshing within the planet’s core. The magnetic pole is moving so quickly that it has forced the world’s geomagnetism experts into a rare move.
On 15 January, they are set to update the World Magnetic Model, which describes the planet’s magnetic field and underlies all modern navigation, from the systems that steer ships at sea to Google Maps on smartphones.

Saturday, December 29, 2018

Boost for Physics at UG

A donation of equipment worth US$40,000 from ExxonMobil has provided some welcome help to the Physics Department at th University of Guyana. Included in the equipment were a diode laser and telescopes. A report at DemeraraWaves said:

"This donation was made following a request after a fire in 2015 destroyed the section of the Faculty of Natural Sciences that houses the equipment for various departments. Among the items destroyed was equipment for the physics laboratory belonging to the Department of mathematics, Physics and Statistics, the Computer Science Department and the specimen collection and equipment from the Department of Biology.
At the handover ceremony Vice-Chancellor of the university, Professor Ivelaw Griffith said the initiative is one which highlights the determination of the department to reinvent itself and build new partnerships while doing so. “It matters; the investment that Exxon Mobil along with the university is making. It recognises the vital importance of rebuilding physics in a significant way – not only quad physics but physics because of its importance to the other enterprises of the university,” he said."

Tuesday, November 27, 2018

First plane propelled by ionic wind

MIT engineers have flown the first plane without moving parts, propelled by ionic wind. Batteries are used to create high voltages which are used to ionize air and use these ions to generate thrust. A report states:

This is the first-ever sustained flight of a plane with no moving parts in the propulsion system,” says Steven Barrett, associate professor of aeronautics and astronautics at MIT.
“This has potentially opened new and unexplored possibilities for aircraft which are quieter, mechanically simpler, and do not emit combustion emissions.”
He expects that in the near-term, such ion wind propulsion systems could be used to fly less noisy drones. Further out, he envisions ion propulsion paired with more conventional combustion systems to create more fuel-efficient, hybrid passenger planes and other large aircraft.
This story has some interesting physics in it.

Sunday, October 28, 2018

Combating climate change - the physics

There is considerable physics underpinning developments in this field. Identifying it and explaining it would be a good exercise for students...
For example these reports:
Climate change: Five cheap ways to remove CO2 from the atmosphere (BBC)
Climate change: Low cost, low energy cooling system shows promise (BBC)

Friday, September 28, 2018

Liquefaction of solid bulk cargo

This article from The Conversation on problems caused by unexpected behaviour of granular materials  in a ship’s hold has some interesting physics behind it.
"Solid bulk cargoes – defined as granular materials loaded directly into a ship’s hold – can suddenly turn from a solid state into a liquid state, a process known as liquefaction. And this can be disastrous for any ship carrying them – and their crew."