From 2c23c3e0dcca1dc43e931043413e075b0443d76d Mon Sep 17 00:00:00 2001 From: tactonbishop Date: Sun, 23 Oct 2022 14:30:04 +0100 Subject: [PATCH] Last Sync: 2022-10-23 14:30:04 --- .../Electromagnetism.md | 2 +- .../Physics_of_electricity/Ohms_Law.md | 24 +++++++++++++++++++ Electronics/Resistance.md | 10 +++++--- 3 files changed, 32 insertions(+), 4 deletions(-) diff --git a/Electronics/Physics_of_electricity/Electromagnetism.md b/Electronics/Physics_of_electricity/Electromagnetism.md index d468752..4b3e44b 100644 --- a/Electronics/Physics_of_electricity/Electromagnetism.md +++ b/Electronics/Physics_of_electricity/Electromagnetism.md @@ -18,7 +18,7 @@ We know that charge is an innate property of all charged fundamental particles. ## Magnetism -> Magnetism is a physical property produced by the _motion_ of electric charge, which of course, is the same thing as [electric current](/Electronics/Physics_of_electricity/Current.md) +> Magnetism is a physical property produced by the _motion_ of electric charge, which of course, is the same thing as [electric current](/Electronics/Current.md) A **magnet** is a material or object that produces a magnetic field. This field is invisible but visible by its effects: pulling on other magnetic materials such as iron, steel, nickel, cobalt etc and attracting or repelling other magnets. diff --git a/Electronics/Physics_of_electricity/Ohms_Law.md b/Electronics/Physics_of_electricity/Ohms_Law.md index e69de29..bcca179 100644 --- a/Electronics/Physics_of_electricity/Ohms_Law.md +++ b/Electronics/Physics_of_electricity/Ohms_Law.md @@ -0,0 +1,24 @@ +--- +title: Ohm's Law +categories: + - Electronics +tags: [physics, electricity, electrical-resistance] +--- + +# Ohm's Law + +The relationship between [current](), [voltage](), and [resistance]() is defined by Ohm's Law: + +> The current flowing from one point to another is equal to the voltage accross these points divided by the resistance between them. + +$$ +I = \frac{V}{R} +$$ + +As an application, consider a circuit with a 9V battery with a 10,000 $\Omega$ resistor attached across its terminals. + +The current flowing through the resistor can be calculated as follows: + +$$ +\frac{9V} {10,000\Omega} = 0.0009 \textsf{A} (0.9 \textsf{mA}) +$$ diff --git a/Electronics/Resistance.md b/Electronics/Resistance.md index 1d479ca..100d4ea 100644 --- a/Electronics/Resistance.md +++ b/Electronics/Resistance.md @@ -17,14 +17,14 @@ The opposite to resistance is **conductance**. Again conductance is not the same ## Factors affecting resistance -- The larger the diameter of an electric wire, the lower the electrical resistance to the current flow. +- The larger the diameter of an electric wire, the lower the electrical resistance to the current flow. (If we use the analogy of electricity as water-flow: the wider the pipe, the more water that can flow.) - As a conductor heats up (e.g. copper, aluminium wire), its overall resistance increases. ## Notation and scientific expression ### Resistance -- We use $R$ to represent resistance/Electronics/Voltage.md +- We use $R$ to represent resistance - The unit of resistance is **ohms** ($\Omega$) > One ohm is the resistance of a circuit or circuit element that permits a steady current flow of one [amp](/Electronics/Current.md#formal-expression) (one coulomb/second) when one [volt](/Electronics/Physics_of_electricity/Voltage.md#voltage) is applied to the circuit. @@ -38,4 +38,8 @@ The opposite to resistance is **conductance**. Again conductance is not the same > Given that resistance is the opposite of conductance, the relation between the two quantities can be expressed via a recipricol: $R = 1/G$ and $G = 1/R$ -## Resistor components +## Resistors + +![](/img/resistor-photo.jpg) + +A resistor is an electrical component that can be used in circuits to introduce specific amounts to resistance where needed. This is typically done in order to temper the total voltage and so keep the current flowing within certain set parameters.