Uses Of Radiation

Tracers A radioactive tracer is used to follow the path of a compound through a system. E.g. Leaks in underground pipes that carry water or oil can be detected by injected radioactive tracer into the flow. Geriger tubes on the surface can then be used to detect the leakage. Medical and biological uses Immature cells and cells that are growing …

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Rube Goldberg Machine

Does the photo above seem complicated to you? A Rube Goldberg machine is a machine that goes the “extra mile” to get a job done, usually including a chain reaction. It is pleasing and mind blowing to watch the machine in action. It takes a long time and a lot of hard work and thought to build such a machine. …

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Meissner effect. – The art of levitation

The Art Of Levitation? The “metal” below is a superconductor that has been cooled by liquid nitrogen to below its transition temperature. The spinning cube above is a magnet. The magnetic field of the magnet is being expelled from the interior of the superconductor, hence levitating the magnet. Brief explanation of what a superconductor actually is:A superconductor is a type …

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Power Dissipation In A Resistive Load

Consider the circuit on the right. Suppose a sinusoidal voltage $V = V_{o} \, sin \, \omega t$ is applied across the resistor of resistance R. The current in the resistor will be $I = I_{o} \, sin \, \omega t$. Both the voltage and the current vary sinusoidally with the same angular frequency ω and they are in phase. The …

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Root-mean-square values

The root-mean-square (r.m.s.) value of an alternating current is equivalent to the steady direct current that converts electrical energy to other forms of energy at the same average rate as the alternating current in a given resistance. The r.m.s. current of an alternating current is also known as the effective current of the a.c. An alternating current ammeter reads the …

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Types of current waveforms & Features Of A.C. Waveform

Direct current means that the polarity of the e.m.f remains constant with time. Current flows only in one direction, hence charge carriers flow in one direction only. Types of direct current waveforms: Alternating current means that the polarity of the e.m.f. changes with time. Direction of current flow in the electrical circuits varies with time in a periodic manner. Direction …

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Alternating Current

This topic covers “Alternating Current” of A Level Physics. (Equivalent to Advanced Placement) Sub-Topics: Types Of Waveform & Features Of An A.C. Graph Root-mean-square values Power dissipation in a resistive load Features of an A.C. transformer Principle Of Operation Of An Ideal Transformer  Energy Losses In Transformer  Power Distribution Rectification Questions:Coming soon!