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When to use I²R, V²/R or VI while calculating Electric Power?

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I came across a question that was asked to me quite a couple of time: When to use I²R, V²/R or VI while calculating power? At first, the question looks simple and as if it needs no formal explanation but that's not the case. Use of any of them will give the correct result provided that you apply it correctly. Correct application is possible only when you understand the type of circuit you are dealing with. Another important point is to use the one which is going to take less time and help you calculate easily. All of the three equations tell the same thing but their usage is subject to the type of problem you're trying to solve. Let us understand when, how an what to use while calculating power in an electrical circuit.

What exactly causes lightning in the clouds and how to avoid them?

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L ightning followed by a thunderbolt is a common phenomenon while it's raining heavily or when it is tending to rain. Lightning strikes are one of the many natural causes common for so many deaths or injuries around the world. About 240,000 cases of lightning strike happen every year around the world and about 6000 people lose their lives every year. As of June 2020, nearly 100-120 people have already lost their lives in northern India due to lightning. But what induces these lightning strikes? Why they are lethal and common? In this article, I will try to explain the cause of lightning in a simple manner and also how to avoid it. Lightning is an electrical discharge phenomenon. Any such thing happens between two opposite electrical charges separated by a distance. The hot air from the ground rises up and cools down to form water and eventually to smaller pieces of ice (due to the freezing temperatures in the upper atmosphere). These water droplets and ice al...

Distribution Factor & Mitigation of Harmonics in an Electrical Machine

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Harmonics in an Electrical Machine is a great problem as it affects the maximum torque in an AC motor and maximum generated EMF in case of an Alternator. Harmonics is generated because of the non-linear behavior of the core material (the material that carries the magnetic field flux) evident from the B-H curve.  Hence elimination or mitigation of Harmonics from the machine is important. This can be done by suitably designing the machine. One such design aspect is the Distribution Factor.  There are two types of winding in an Electrical Machine, Concentrated Winding and Distributed Winding . The term 'Distribution Factor' comes from Distributed type of winding. Let's understand the difference between the two and how Distribution Factor in a Distributed Winding can help in eliminating Harmonics of nth order. Download PDF Another Design aspect responsible for mitigation of Harmonics is Pitch Factor. Click here to know more about Pitch Factor.