Skip to main content

Electric Charges and Forces - Coulomb's Law - Polarization

The modern picture of an atom is a nucleus which is very small compared to the size of the atom.And if the atom is neutral the number of electrons and the number of protons is the same.If you take electron off you get a positive ion.If you add an elentron then you get a negative ion. The charge of the electron is the same as the charge of the proton.That's why the number is the same for neutral  atoms. 

Electrostatics deals with forces between charges.  Static means the charges are not moving, or at least a re not moving very fast. 
How fast is "not very fast"? 
When a charge moves, it generates a magnetic field, which can lead to a magnetic force. As we begin our study of electricity, we want to minimize complexity and focus just on electric force. To keep things simple, we let charges stand still, or move very slowly. So "not very fast" means motion so slow the magnetic effects are insignificant compared to the electric forces. 

Charge 
The concept of charge arises from an observation of nature: We observe forces between objects. Electric charge is the property of objects that gives rise to this observed force. Like gravity, electric force "acts at a distance". The idea that a force can "act at a distance" is pretty mind-blowing, but it's what nature really does.Electric forces are very large, far greater than the force of gravity. Unlike gravity, there are two types of electric charge, (whereas there is only one type of gravity; gravity only attracts). 


Consider a system of two point charges, q1 and q2,  separated by a distance r in vacuum. The force exerted by q1 on  q2 is given by Coulomb's law: 



Note that electric force is a vector which has both magnitude and direction. In SI units, the Coulomb constant Ke is given by
Where
is known as the “permittivity of free space.” Similarly, the force on q1​​ due q2​​ to  is given by

The modern picture of an atom is a nucleus which is very small compared to the size of the atom.And if the atom is neutral the number of electrons and the number of protons is the same.If you take electron off you get a positive ion.If you add an elentron then you get a negative ion.
The charge of the electron is the same as the charge of the proton.That's why the number is the same for neutral  atoms.

Electrostatics deals with forces between charges.  Static means the charges are not moving, or at least are not moving very fast.
How fast is "not very fast"?
When a charge moves, it generates a magnetic field, which can lead to a magnetic force. As we begin our study of electricity, we want to minimize complexity and focus just on electric force. To keep things simple, we let charges stand still, or move very slowly. So "not very fast" means motion so slow the magnetic effects are insignificant compared to the electric forces.
Charge
The concept of charge arises from an observation of nature: We observe forces between objects. Electric charge is the property of objects that gives rise to this observed force. Like gravity, electric force "acts at a distance". The idea that a force can "act at a distance" is pretty mind-blowing, but it's what nature really does.Electric forces are very large, far greater than the force of gravity. Unlike gravity, there are two types of electric charge, (whereas there is only one type of gravity; gravity only attracts).

Force between charges: Coulomb's Law of electric force
Coulomb's Law very nicely describes this natural phenomenon. The law has this form,

The Electric Constant, ϵ 0 \epsilon_0 ϵ 0 ​ \epsilon, start subscript, 0, end subscript , the permittivity of free space
K, the constant of proportionnality , frequently appears in this form,
Coulomb's Law describes something that happens in nature. The electric constant, ϵ 0 \epsilon_0 ϵ0​\epsilon, start subscript, 0, end subscript, describes the experimental setup and the system of units. "Experimental conditions" refers measuring F ⃗ \vec F F F, with, vector, on top on point charges (or something that acts like a point charge, like charged spheres). In the SI system of units, ϵ 0 {\epsilon_0} ϵ0​\epsilon, start subscript, 0, end subscript is experimentally measured to be,    
ϵ0​=8.854187817×10−12\epsilon, start subscript, 0, end subscript, equals, 8, point, 854187817, times, 10, start superscript, −, 12, end superscript coulomb 2 / ^2/ 2/squared, slash newton-meter 2 ^2 2
This value of make, K=4πϵ0​1​=4π⋅8.854×10−121​=9×109
The dimensions of K K KK are: newton-meter 2 / ^2/ 2/squared, slash coulomb 2 ^2 2squared .

Comments

Post a Comment

Popular posts from this blog

Lab 2 , 3 , 4 Method math in java

Class Teedcalculator: /*  * To change this license header, choose License Headers in Project Properties.  * To change this template file, choose Tools | Templates  * and open the template in the editor.  */ package teedcalculator; import static teedcalculator.Oparetor.tand;// to access all static Tand of a class import static teedcalculator.Oparetor.tan;// to access all static Tan of a class import static teedcalculator.Oparetor.cost;// to access all static Cost of a class import static teedcalculator.Oparetor.cosd;// to access all static Cosd of a class import static teedcalculator.Oparetor.degree2;// to access all static Degree of a class import static teedcalculator.Oparetor.divide;// to access all static divide of a class import static teedcalculator.Oparetor.minus;// to access all static minus of a class import static teedcalculator.Oparetor.modulo;// to access all static modulo of a class import static teedcalculator.Oparetor.multiply;// to acce...
Post a Comment
Read more

Barometric pressure sensor with Arduino

Hardware Required - Arduino or Genuino board - SCP1000 Pressure Sensor Breakout Board - hook-up wires  Procedure  Follow the circuit diagram and make the connections as shown in the image given below. Arduino Code /******* All the resources for this project:   https://lihuo.blogspot.com *******/ The code below starts out by setting the SCP1000 's configuration registers in the setup() . In the main loop, it sets the sensor to read in high resolution mode, meaning that it will return a 19-bit value, for the pressure reading, and 16 bits for the temperature. The actual reading in degrees Celsius is the 16-bit result divided by 20.   Then it reads the temperature's two bytes. Once it's got the temperature, it reads the pressure in two parts. First it reads the highest three bits, then the lower 16 bits. It combines these two into one single long integer by bit shifting the high bits then using a bitwise OR to combine them...
2 comments
Read more

Software Arduino IDE

Arduino is an open source computer hardware and software company, project, and user community that designs and manufactures single-board microcontrollers and microcontroller kits for building digital devices and interactive objects that can sense and control objects in the physical world. A program for Arduino hardware may be written in any programming language with compilers that produce binary machine code for the target processor. Atmel provides a development environment for their 8-bit AVR and 32-bit ARM Cortex-M based microcontrollers: AVR Studio (older) and Atmel Studio (newer). IDE The Arduino integrated development environment (IDE) is a cross-platform application (for Windows, macOS, Linux) that is written in the programming language Java. It originated from the IDE for the languages Processing and Wiring . It includes a code editor with features such as text cutting and pasting, searching and replacing text, automatic indenting, brace matching, and syntax highl...
Post a Comment
Read more