A Level Maths Teaching.

 As well as covering the sciences, we also cover Maths at both GCSE and A Level. Many of our students struggle with some of the harder concepts such as Trig Equations and solving them. This weeks A level Maths lesson dealt with this problem showing approaches to solving these problems without resorting to the answers or begin told this is the way to do this one. Students need to learn these techniques so that they can become better

Glycolysis A level Biology

In today's A level Biology Video we looked at Glycolysis, the Link reaction, The Krebs cycle and Oxidative Phosphorylation. The process of Glycolysis breaks down glucose into 2 3 carbon sugars only producing a small amount of energy. The link reaction does a little more, but the Krebs cycle makes the most energy and this is in all forms of energy chemicals. These are all turned into ATP the energy molecules by the process of oxidative phosphorylation.

Transpiration and the Potometer

Looking at how plants take up water is an essential experiment in Biology. A small piece of plant in this case some water cress is inserted into a tube at the top making a water tight seal. The potometer shown here allows an air bubble to be brought into the apparatus, using a syringe, so that the movement of the bubble can be monitored with time. As the plant transpires, water is sucked up the tube and evaporates from the leaves. By knowing the volume of the capillary tube the amount of water lost be minute can be calculated.

Carbon Nanotubes

Three allotropes of Carbon, Diamond, Graphite and Buckminster Fullerene are known.

There is another, a one slice of graphite (graphene) that is rolled into a tube to make a carbon nanotube called a carbon fibre.

This model was created by me since a manufactured model didn't exist.  I made a sheet of graphene three carbons joined to each other then rolled it up like the real thing. The tube is incredibly strong .

Making Silver crystals

Making small crystals of silver from a solution of  Silver Nitrate and a piece of copper wire

Getting the system setup

First we wrapped the wire around a pencil to make a coil. This creates a larger surface area and produces more silver.

Next the solution 0.1M Silver Nitrate is added to cover the copper coil in a test tube. This is then left in a dark place for an hour or so.

After about an hour the test tube is take of of the dark and here we can see the copper wire has changed colour. The solution has gone a light blue and crystals have formed.

We then place this under the microscope.

and take a few pictures of what we see.

and sure enough some crystals are formed. The longer you leave this the better and bigger the crystals.

Measuring the speed of Sound in a Column

In this experiment I have taken a tuning fork, a hollow tube and a measuring cylinder filled with water. The hollow tube can move up and down creating a length of air in the column above the water. The tuning fork is placed over the column and the column moved up and down until the loudest sound is heard. The length of the tube is a quarter of the wavelength, so we multiply the column  length by 4.

We know that the velocity = frequency x wavelength

So if the column is 19.4cm long then the wavelength is 19.4 x 4 = 77.6

The frequency of the tuning fork is 440Hz

So the velocity = 0.776 x 440 = 341.44 m/s

https://www.youtube.com/watch?v=G7yl43Zvy8E

New A Level Courses

This week we launched our A level Topic by Topic Series, covering Maths, Chemistry, Physics and Biology. These are a series of live streamed lessons covering these core subjects. Each week we take a different topic and try to explain it simply using experiments, models and hands on teaching. Join us on Wednesday and Thursday Mornings.