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The formula for efficiency is:
efficiency = (useful energy / total energy)
Therefore, first we must find the total energy which is the sum of all of the branches of the Sankey diagram. So take the energy specified at each branch and add them to find a total.
The useful energy will be the energy specified by the branch which does not turn off to one side- it carries on straight forwards. For example, in a circuit with a light bulb, the useful energy will be the light energy.
Divide the useful energy by the total energy and you will get the efficiency which should be between 0 and 1. Multiply by 100 to find the percentage efficiency.see more
Scientists originally thought that atoms were like a 'plum pudding' in that they were a sphere of positive charge with negatively charged electrons scattered about inside it. This was because they observed from experiment that the atom was neutral and also that it contained electrons. Therefore the negatively charged electrons must be cancelled out by a positive charge.
However, a scientist named Rutherford proved this model wrong by firing positively charged particles named alpha particles at some atoms in gold foil. Most of the alpha particles went straight through the foil but some were deflected back the way they had come.
This lead to our current model of the atom where most of it is empty space, allowing most of the particles to pass straight through. The nucleus is a positively charged collection of protons and neutrons (which have no charge) and so repels the positively charged alpha particles. The electrons surround this nucleus in rings.see more
When two atomic nuclei are heated to a very high temperature and high pressure, for example inside a star, their nuclei can join to make a larger nucleus. Energy is released when this fusion takes place and the new nucleus is a different element to the original nuclei. For example, inside our sun two hydrogen nuclei can fuse to form one helium nucleus. This fusion can then happen with largerr nuclei to form larger elements like carbon.see more