More Electrostatics

For the last two weeks or so, we have been talking about electrostatic in class. Electrostatics is the study of the electric charges and fields. Shocking stuff. In class, we have learned that objects are attracted or repelled from each other based on their charge. We have learned a lot of different equations to calculate force and charge between objects. One is the inverse square law, which states that the force on an object will be inversely proportional to the square of the distance between two objects. What this means is that the further away an object is from another object, the less force there will be on that object. Inversely, the closer to an object is to another object, the greater the force on that object. This can be represented with the equation F=(proportional to) 1/r².

In the picture below, my phone is 4 inches from my wallet.

In the next picture, my phone is 6 inches from my wallet

Because my wallet is further away in the second picture, the force on my phone is greater in the first picture than the second.

Electrostatics

In class this week, we have been talking about all things pertaining to electrostatics and what not. Electrostatics is the study of electric charges and fields. We learned all objects either have a positive, negative, or neutral charge. Like charges repel each other, for example, to positively charges would repel each other. Concurrently, opposite charges attract each other. Also, both positive and negative charges are attracted to neutrally charged things, but neutral objects remain neutral to each other. Attraction and repulsion both happen when electrons are distributed between objects, because all objects tend to want to be neutral.

All objects can be identified as insulators, conductors, or semiconductors. An insulator is an object that does not easily conduct electricity. Conductors are materials that transmit electricity. Semiconductors are materials that transmit electricity somewhere between that of an insulator and a conductor.

Above is a picture of a metal knife and a rubber spatula. The knife is a conductor, because it is metal, and metal transmits electricity well. The spatula is an insulator, because it is rubber, and rubber doesn’t transmit electricity. This is why it would be more dangerous to stick a metal knife into an outlet, than a rubber spatula.