Equation of a Circle

 Using the equation of a circle and a point on the circle to work out the equation of a tangent.

BSC Expo

 Having a day off visiting the @BSC_EXPO in London. Checking out some new equipment to buy for the film making

Ninja star 2

Unlike the last Ninja star video where the Ninja star is on the VdGG this time its the electrons from the Ninja star that are being used to neutralise the charge on the Van de Graaff generators dome and this causes motion.

The Ninja Star

The Ninja Star is actually called a Hamilton's mill but in physics it's called a Electrostatic pinwheel. The reason it gets spinning is because the spinner is positively charged, like the dome. Each point has a strong electric field around it. Air molecules close to the points lose electrons and become positively charged ions - their electrons were attracted to the points and used to neutralise some of the charge on the dome. Positively charged ions are repelled by the positive star's points and move away. The points move in the opposite direction (Newton's 3rd law) so the star Spins.

Thermoelectric Converter

Having some fun with the thermoelectric converter, Ice cold water on one side and near boiling water on the other and getting the fan to spin for quite a while, then repeating with different temperatures in both and timing the fan movement.

Sonometer

Using a sonometer to tune a string to a particular frequency using a paper hanger, looking at the relationships between length, tension and thickness on the pitch.

Covalent Bond Revision

 Using @snatoms to help with GCSE Chemistry Revision. The models are so quick to made and the students really enjoy these so much more than other s we have. We made dozens of models in a few minutes.