There are 2 different types of charges. there are protons and electrons.
Protons are positively charged and electrons are negatively charged
Like charges repel and opposite charges attract.
Direct contact: This is when objects touch each other and charges transfer throughout to even out. An example is when a person touches you and manages to shock you, that is the electrons transferring.
Friction: when an object rubs against another object it steels electrons from it making one object have more electrons and the other with more protons. When you are wearing a ski cap and take it off, the cap steels electrons from your hair making it stick out and attract to the cap.
Induction: This is where you are able to separate charges from a neutral object without touching it. When you bring a negatively charged metal near a neutral object, the electrons will try and get further from the metal bar, while the protons want to get closer, then if you link the neutral object to the ground, the electrons will escape leaving the object positively charged. the process of separating the positive charges from the negative in a neutral object is called polarization.
Electric Fields
An electric field is a region around a charge that can push or pull another charge, as the object gets further from the electric field the influence is weaker. The reason why electronics are safe in a metal box is because the metal box creates it's own electric field which will not allow any other fields or charges influence the electronic device.
Electric Potential:
Electric potential is different than electric potential energy. Electric potential is voltage. An equation for Electric Potential is v= pe/q. which is measured in volts.
Capacitors are found in the camera's flash section.
The reason why the flash cannot go on continuously is because the capacitor has 2 oppositely charges plates which are charged, and as enough difference in potential energy is built between the 2 plates, they come in contact for less than a second causing the flash, then it has to charge up again for a couple of seconds until it can repeat the process.
Ohm's Law and Current:
Current can only be present in a complete circuit where electric potential difference is present therefore voltage is present. The two types of current are:
- AC current, where current vibrates back and forth in its same position
- DC current, where current moves in one direction
Current is directly proportional to Voltage and inversely proportional to resistance according to Ohm's Law, therefore I = V/R
Different countries has different amount of volts coming out of its appliances, therefore the object in that country have the resistance set for the according voltage it is supplied with, to produce the wanted current. So if an object that was created in America is plugged into a European outlet, the object will get destroyed as the resistance is low and the voltage is high, causing the current to be too much.
Circuits
There are two different types circuits, the first one is a series circuit where all the appliances are linked together in one lane, and the more appliances are added the greater the resistance which affects all of the current running through the appliances. A parallel circuit is a circuit where the appliances have different lanes of wire therefore the more lanes you open, each appliance's current does not change, and the overall resistance decreases allowing to provide the full amount of current needed for each appliance.
Homes are equipped with parallel circuits.
A fuse is usually put at the start or the end of a parallel circuit, so that if too much current is going through, where the appliances might be in danger a wire in the fuse will melt causing the circuit to disconnect, not allowing any current to pass by.
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