Photosynthesis

Having brought some pond weed in from the pond for a few days and given it some light, the plants performed well, giving off a stream of oxygen bubbles that could be counted and the oxygen tested for. We tried different light sources and different wavelengths using led bulbs.

 

Networking

 

Networking. Dusting off some 25-year-old PowerPoint. The Network slides have stayed the same in that time.

Measuring the River Flow

Measuring the river flow rate in  The River Gade. This involved a little wading. The water was at 8.9C Now to build up a cross-sectional flow map of the River to explain the distribution of organisms.

 

Iodine in water and cyclohexane

 

First, Iodine was dissolved in water and a little dissolved, changing the colour, but much of the iodine remained solid. Then it was shaken with cyclohexane, and immediately, the water layer went clear as the iodine dissolved in the cyclohexane. After a while, more iodine dissolved in the water, turning it brown again.

Protecting the sensor

 We are doing some Simple Harmonic Motion experiments online with springs and masses over the @pascoscientific Ultrasonic sensor, so we are trying to keep it safe.

Differentiation from First Principles

 Trying to understand differentiation from first principles is one of the hardest things to learn. Giving the students these proofs and then letting them do one on their own shows whether they have grasped the concept.

Calculation of Wavelength

Physics practical working out the wavelength of a laser going through a diffraction grating of 100 lines per mm. Managed to get 667nm, which was pretty close.