It is tempting to regard the equations for electric fields and electric potentials as being separate things but they are so closely related that they are best viewed as different sides of the same coin. This is because electric field strength is the same as potential gradient. Or to put it another way, the electric … Continue reading Electric Field & Electric Potential
Key Facts: (Electro)Magnetism
With only the final Physics paper left to be sat in the this year's AQA Trilogy exams, you should now be giving your revision a final push. Magnetism and electromagnetism is a fairly compact stand-alone topic and is the ideal candidate for a quick refresher. The knowledge you need can be divided into six areas … Continue reading Key Facts: (Electro)Magnetism
Key Facts: Electric circuits
Electricity is one of the forms of energy transfer so it is not surprising that the definition of the volt (the unit for measuring potential difference) is the energy carried per unit charge. In symbols, where Q is the symbol for charge, this relationship is written as; V = E / Q It is important … Continue reading Key Facts: Electric circuits
Key Facts: Renewable Energy
Examination boards are very keen on asking students to apply their knowledge to real-world situations. One of the most important issues in the world today is climate change and one of the most important ways to address this is by switching from non-renewable energy sources to renewables. BP, which has long been thought of as … Continue reading Key Facts: Renewable Energy
Electric Motors
Having covered Fleming's Left-Hand Rule previously, we will now apply its general principles to the specific application of an electric motor. In particular, we will look at how the sideways motion due to a linear force, as predicted in Fleming's Left-Hand Rule, can be used to produce continuous rotation. We will be focusing on a … Continue reading Electric Motors
Investigating I-V Characteristics
Many GCSE Physics courses, including AQA Trilogy, include a compulsory practical to investigate the current-voltage (I-V) characteristics of various electrical components. This experiment links back to the work done by Georg Ohm, whose results have previously been summarised as; "the current flowing through a conductor is directly proportional to the potential difference (voltage) across the … Continue reading Investigating I-V Characteristics
Ohm’s Law
Potential difference (voltage) and current are fundamental measurements for electric circuits. Multiply the potential difference across a device by the current flowing through it to get the power rating for that device.Multiply the power rating by the time for which the device is used to get the energy that the device has transferred. All of … Continue reading Ohm’s Law
Resources for Electricity Generation
In school we talk about different ways to generate electricity as a potential exam topic but it's much, much more important than that. Russia's war with Ukraine has brought this fact sharply into focus as people start talking about a boycott of Russian oil and gas. At the same time, the UK is phasing-out its … Continue reading Resources for Electricity Generation
Energy Transfers in Electric Circuits
The amount of energy transferred in an electric circuit can be calculated by multiplying the current, time and potential difference. This is expressed in the equation given below. Current is measured in amps (amperes), time is in seconds, and potential difference in volts. Remember that the symbol for current is the letter I - not … Continue reading Energy Transfers in Electric Circuits
Magnificent moles
You may well ask, what is the point of an SI unit that measures “amount”? Surely if we want to know an amount then we simply count whatever it is that we need to quantify. That’s fine until we get to VERY large numbers. How large? We’re talking here about numbers that are massively bigger … Continue reading Magnificent moles
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