Electrostatic Forces Flashcards
What do static electricity sometimes creates forces to do?
It sometimes creates forces that cause your hair to stand up on end or creates little sparks that tingle.
How do objects usually become charged and what is the charged called?
Objects usually become charged by the addition or removal of electrons. This charge is called an electrostatic charge
What happens once an object gains an electric charge?
Once an object gains an electric charge, it remains ‘static’ or stationary on that object. Only in conductors (mainly metals) do charges move through the object creating a ‘current’ of charge rather than a static charge.
How can an object gain an electrostatic force?
There are two ways that an object can gain an electrostatic charge: by friction or by contact with another object that is already charged.
What happens when you rub a neutral material against another?
Rubbing a neutral material against another can add or remove electrons.
What is an example of rubbing a neutral material against another?
When you rub a plastic ruler with wool, for example, electrons from atoms on the surface of the neutral wool are forced onto the neutral plastic ruler. The wool, having lost electrons, becomes positively charged. The plastic ruler, having gained electrons, becomes negatively charged.
What happens when a neutral material is touched by a charged object?
If a neutral material is touched by a charged object, electrons can be transferred from atoms on the surfaces of the two objects.
What happens when a charged object is removed from a neutral material?
When the charged object is removed, the previously neutral material has gained or lost electrons and so becomes charged itself.
Why are electrons the easiest particles to add or remove from atoms?
Electrons are the easiest particles to add to or remove from atoms, because they are not held tightly in the nucleus as protons are.
Why does using a cloth to wipe over furniture can sometimes makes matters worse?
Rubbing leaves the surface with a static charge that can attract small dust particles in the air. The dust particles are neutral and will be attracted to either a positive or negative charge left on the furniture.
How to solve the situation of “using a cloth to wipe over furniture can sometimes make matters worse”?
Using a furniture polish reduces the attraction between the furniture and dust particles by helping any built-up charge to leak into the air.
What can a like charge do?
A charged object can push or pull other charged objects near it. Like charges repel one another while oppositely charged objects attract one another.
Where do forces of attract and repulsion not reply on contact?
These forces of attraction and repulsion do not rely on contact between the two charged objects, just as two magnets do not need to be touching to exert a force on each other. In the same way that magnetic fields are used to explain how magnetic forces can exist without contact, electrostatic forces can be explained by electric fields.
What do the area around charges carry?
The area around charged objects carries an electric field. The electric field lines are closest together near the charged object where the force is strongest.
Examples of charged objects and neutral objects being attracted to each other?
A charged plastic pen attracts a neutral stream of water. A charged balloon sticks to a neutral wall. A charged comb will make dry hair stand up. The illustration below shows how a negatively charged plastic pen is able to pick up a small, neutral piece of paper.
