No displacement can?

A displacement can is usually used to investigate Archimedes Principle. It is used to deliver displaced liquid into a waiting beaker for weighing.

However if no displacement can is available a beaker can give a good result if precautions are used.

Firstly some petroleum jelly is smeared under the 'spout'.

Secondly the small beaker used to catch the over flow needs to be close and under the 'spout' as shown in the diagram.

Some Modern Physics videos

Some vidoes I found useful:
Millikan's oil drop experiment to find e - an good animation of the experiment
Specific charge on the electron e/m - a good video of an actual demo

Do-it-yourself: centripetal force

This device demonstrates centripetal force. Just hold it vertically and whirl it gently so that the top weight circles around. Speed up the motion and the bottom weight rises as the centripetal force increases.

I used a pair of old keys as weights. Takes a bit of practice but is easy enough.

Materials: drinking straw, sewing thread, two weights. A glass tube or plastic tube should also work instead of the straw.

Do-it-yourself lab equipment

I will be periodically (hopefully once per month) adding ideas for making simple equipment for use in the Physics lab or for demos.

Workshop for Physics teachers

On November 4th NCERD held a one-day Workshop in Georgetown for Physics teachers. The workshop was opened by the Minister of Education who spoke on the issues and need for upgrading of science and mathemetics education and Physics in particular. The Director of NCERD, Mr Goolsaran, also spoke to this theme.

Professor Kunar then used a MIT Physics video by Dr Lewin to show some teaching techniques. This was followed in the afternoon by Physics demonstrations using simple equipment by Prof. Kunar.


The workshop is mentioned in this Kaieteur News article.

Links
Lectures by Dr Lewin

From the other blog

Two items recently posted on my other blog which relate to Physics education:

Intertropical Convergence Zone in September

Education on the rise world-wide

Morning mist

I shot this picture before dawn on the 20th.

Such mist is not common here but I have noticed it several times lately. It indicates that the air was very humid and that rapid cooling occurred overnight - probably because the sky was clear.

Clouds reflect heat, both incoming and outgoing. If the sky is clear at night the ground can lose heat quickly by radiating it to space.