103 lines
2.3 KiB
Markdown
103 lines
2.3 KiB
Markdown
## Farad
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Measures capacitance, the ability of a body to store an electrical charge.
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1 Farad = the ability to store 1 couloumb
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Term | Symbol | Weight
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-----------|----|------
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Picofarad | pF | $10^{-12}$
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Nanofarad | nF | $10^{-9}$
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Microfarad | $\micro$F | $10^{-6}$
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Milifarad | mF | $10^{-3}$
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Farad | F | $10^0$
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Kilofarad | kF | $10^{3}$
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## Couloumb
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1 coulomb is the electric charge transported within one second through the cross-section of a conductor in which an electric current of the strength of 1 ampere flows.
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## Henry
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Measures electrical Inductance
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$\displaystyle V(t)=L{\frac {dI}{dt}}$
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## Volts
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Measures electric potential
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## Amperes
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Measures electric current
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## Ohms
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Measures resistance
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Term | Symbol | Weight
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Nanoohm | n$\ohm$ | 10-9
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Microohm | $\micro \ohm$ | $10^{-6}$
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Milliohm | m$\ohm$ | $10^{-3}$
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Ohm | $\ohm$ | $10^{0}$
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Kiloohm | k$\ohm$ | $10^{3}$
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Megaohm | M$\ohm$ | $10^{6}$
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Gigaohm | G$\ohm$ | $10^{9}$
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## Hertz
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Measures frequency
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Term | Symbol | Weight
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----------|------- | -----
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Hertz | Hz | $10^0$
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Kilohertz | kHz | $10^{3}$
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Megahertz | mHz | $10^6$
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## Watt
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Measures Power
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$Power = V * I = \frac{V^{2}}{R} = I^{2}R$
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Joules per Second
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Term | Symbol | Weight
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-----------|----|------
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Nanowatt | nW | $10^{-9}$
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Microwatt | $\micro$W | $10^{-6}$
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Milliwatt | mW | $10^{-3}$
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Watt | W | $10^{0}$
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Kilowatt | kW | $10^{3}$
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Megawatt | MW | $10^{6}$
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Gigawatt | GW | $10^{9}$
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**Examples:**
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Device | Power
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-------|----------
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Arduino| 167mW
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Laptop | 1.5W
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House | 2.2kW
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# Decibel
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A decibel ($dB$) is used to describe the ratio between two values, it is calculated as $\displaystyle 10\log{10}{\frac{V1}{V2}}$
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Here are a few commonly used values
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| db Value | Power Ratio (10logA) | Voltage/CurrentRatio (20log(A)) |
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| ---- | --- | ---- |
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| -20dB | 0.01 | 0.1 |
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| -10dB | 0.1 | 0.3162 |
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| -6dB | 0.25 | 1/2 = 0.5 |
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| -3dB |1/2 = 0.5 | $1\sqrt{2} \approx 0.707$ |
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| -1dB | 0.79 | 0.89 |
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| 0dB | 1 | 1 |
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| 1dB | 1.26 | 1.1 |
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| 3dB | 2 | $\sqrt{2} \approx 1.414$ |
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| 6dB | 4 | 2 |
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| 10dB | 10 | $\sqrt{10} \approx 3.162$ |
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| 20dB | 100 | 10 |
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| 30dB | 1000 | 31.62 |
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# Decade
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Related to Frequencies
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One decade is a distance along the frequency line, for example $1 \rightarrow 10$ or $10 \rightarrow 100$
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