# What is Electrostatic Force ?

In this lesson we study electrostatic force electrostatic force can be an attraction or a repulsion so we need to understand when are objects pulled together when are they pushed apart electrostatically you can investigate this yourself very easily.

## What is Electrostatic Force ?

for example by taking two balloons if you rub both the balloons against the same kind of cloth maybe you have a woolen Jersey and you rub both of them against that woolen Jersey and then you hold them on their string so that they free to move and you look at how they interact with one another then you will be able to see how like charges interact do they're tracked or do they repel one another.

how do we know that these would be like charged because we've treated them the same way we rub them both against the same kind of material and so they must end up with the same charge maybe they might both end up with a positive charge perhaps.

if they hold their electrons more tightly than the Jersey does and if you do this you'll see that they will move apart from one another it'll be like they'll run away from one another and you can chase one with the other and that's because positive objects repel other positive objects now

you don't know perhaps when you rub them both with the same material they both ended up negatively charged you can't know that just by rubbing them you'd have to know some other information to know whether it was positive or negative.

but you just know that they both got the same charges one another because you treated them the same so perhaps there's material that you rub them with holds its electrons looser than the balloon then the balloons will both end up negatively charged to negatively charged.

balloons will also repel one another negative and negative are the same as one another we can say there are like charges positive and positive are also like charges and like charges repel one another now let's say instead you were to rub one balloon with one kind of cloth and another balloon with something else then

there is the possibility that you could charge the two balloons differently to one another one positively the other negatively that won't necessarily happen but it might if you get that right you will find that the balloons now attract one another and that's because opposite charges attract positive and negative attract one another

now actually all positive objects have both positive and negative particles in it and the same with all negative objects so all kinds of objects will attract one another because there will be particles inside them that will attract one another so that plus will attract that minus that class will attract that -

for example and that class will attract that - and all the others not shown as well I haven't shown all the possibilities of attraction but the point is that any two objects do have oppositely charged particles inside them which attract one another similarly any two objects also have like charges which will repel one another that positive will repel that positive that negative will repel that negative and so on and I haven't shown all the possibilities of course

but what determines whether the object overall attract or repel is the relative strength of the attraction and repulsion so when there are oppositely charged objects they attract one another more than they repel one another when they are like charged objects they repel one another more than they attract one another and so the overall effect is attraction for the positive and negative objects if oppositely charged objects and repulsion for the like charged objects

## How does plastic comb attract paper pieces ?

Topic electric charge how does a plastic comb attract paper what you don't believe me okay
let us try take a plastic comb and bring it close to some pieces of paper hey wait  we need to do something first rub the comb on your dry hair

And then bring the comb close to the pieces of paper see I was correct the pieces of paper got attracted to the plastic comb do you think it is magic no the reason behind this is electric charge electric charge is the quantity of electricity held in an object

## There are How many types of Electric charge ?

there are two types of electric charges -positive and negative however there are
some objects where the positive and negative charges are equal to one another.

in such cases we say that the object is electrically neutral so was the plastic comb initially electrically neutral or electrically charged initially the plastic comb was electrically neutral.

that means it had the equal number of positive and negative charges hence it did not have the ability to exert a force and attract the pieces of paper so after rubbing the plastic comb on our dry hair why was it able to attract the pieces of paper I will tell you why when we rub the plastic comb on our dry hair it gained an electric charge once it got electrically charged it got the ability to exert a force on the pieces of paper and attract them this charge is called as static electricity

however do you think like a plastic comb a metallic comb would also attract the pieces of paper
nope you are wrong a metallic comb will not attract the pieces of paper like the plastic on wondering why is that so it is because plastic is not a good conductor of electricity it does not
allow the electric charges to flow through it onto the earth as a result the charge is built in the plastic comb making it electrically charged and enabling it to attract the pieces of paper

however metal is a good conductor of electricity it does not let the charges build in it it allows the electric charges to flow through it onto the earth thus not allowing the metallic comb to get electrically charged as a result the metallic comb does not attractive pieces of paper