What causes like charges to repel?

Question

And where does the energy that moves repelling magnets come from?

Answer 1

There is a field around any charge. Field can be represented by lines of forces. The lines of forces are the path along which any positive charge will move. These lines of forces always end in a negative charge. If there is no negative charge they end at infinity.

No two lines of forces cut each other.

When two like charges are nearby, the field or the lines of forces of these charges has to find their way in between these two charges and at the same time they should not cut each other.

This is possible only when these two charges are separated from each other. The process of separation continues for ever, because the lines of forces or field from each charge are spread across, from the charge to infinite distance.
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The explanation for magnetic repulsion is similar to the above but for the filed. Magnetic fields are closed. There is no beginning or end for magnetic field. The cause of repulsion is the same as above.

Answer 2

The energy comes from the force of the fields around the particles. Both charges generate a field. A field is simply an area where objects with the right properties (in this case charge) feel a force. In this universe, like charges do not want to be together- that's the model of reality we operate on.

Answer 3

From the Electric Field and Magnetic fields

Answer 4

Everything is made of particles and these particles have electrical charges – they can be positive, negative, or neutral. Atoms can be thought of as the basic building blocks of everything in the universe. They have three components: electrons, protons, and neutrons. Electrons have a negative electric charge and we usually associate these particles with electricity. Protons have a positive electric charge, and neutrons are neutral which means they have no electric charge. Atoms normally have the same number of protons and electrons. The negative charge of the electron cancels out the positive charge of the proton giving the atom a zero net (or neutral) charge. Atoms with an electric charge are called ions. These ions either have more protons than electrons and so have a positive charge or have more electrons than protons and have a negative charge.

The protons and neutrons are glued together in what is called the nucleus (center part) of the atom. The electrons are rapidly moving around outside of the nucleus kind of like a swarm of bees (the hive would be the nucleus). However, the bees in reality would be a long way from the hive. In fact, if the hive (nucleus) were the size of a basket ball, the bees (representing the electrons) would be swarming around the outside as far as a mile away. In other words, the electrons take up almost all of the space of an atom. The next closest nucleus would be a mile away. The nuclei of atoms are locked inside the atom and are not free to travel to other atoms. However, the swarming electrons are free to move. In fact they are freer to move in some substances than others.

Electrons may travel from one material to another just by contact. This is because some materials have a greater “like” for electrons and will “steal” electrons from materials with a lesser “like” for electrons. For instance, a plastic spoon has a greater “like” for electrons than cotton. When rubbed together, the plastic spoon will attract and steal electrons from the cotton. This means the spoon has a greater number of electrons than protons making it have a negative charge. Since the cotton lost some electrons, it is now positively charged .Saran Wrap has even a greater like for electrons than plastic spoons. When rubbed together, the Saran Wrap “steals” electrons from the spoon making the spoon positive. However, only so many electrons can be “stolen” because the substance becomes more positive from losing electrons and holds on to its remaining electrons even harder. If two materials have the same electric charge they will “not like” or repel each other (push each other away). If they have opposite charges, they will “like” each other causing them to be attracted so they come together.

A neutral object, one with equal numbers of protons and electrons, can also appear to be and behave as if it is charged, by having its charges rearranged. This is called charge by induction. This can happen in materials that are poor conductors of electric charges, such as foam, when they are close to highly charged objects. For example if you bring a highly negatively charged object, such as a plastic spoon near a neutral poor conductor, such as a foam peanut, the positive charges in that peanut will collect on the end nearest to the spoon, because the positive charges in the peanut are attracted to the negative charges in the spoon. The foam peanut is now charged by induction, even though overall it is still neutral .

We're familiar with electric charges from: electricity we use everyday, rubbing your feet on carpet to build up a charge to give a shock, and making your hair stand up by rubbing a balloon on it. The human body can detect large electric fields. Although the body is neutral (net zero charge), sometimes the positive or negative charges can move to one side of a body part giving it a charge. This charge by induction causes hair to stand up (every hair repels each other since they have the same charge). During thunderstorms, some people feel their hair standing up due to their bodies becoming charged by the induction because of the charged cloud above them. This is actually a very dangerous situation as it means that they are likely candidates for a lightning strike and should seek shelter if possible.
Different particles have different charge properties and particle physicists use these charges to identify different particles and study their interactions. For example, if you know that one particle is negatively charged and another particle is repelled by it, then you can infer that this particle is also negatively charged.

The materials used in this exercise are nonconductors – charges do not move easily through them. Some everyday nonconductors are rubber and plastic. This means electrons will not travel very far within the material, but will move between surfaces that are in contact. The charges are static (unmoving) and nonconductor materials keep their charges for a while. These experiments work best in dry air. Humidity makes these experiments difficult because water vapor is a polar molecule which means that it is attracted to anything that has a charge and so the water molecules will steal charges off any material. When there is less water vapor, materials can retain charges for longer periods of time making winter an ideal time to perform these experiments. If it is humid, use a hair dryer to dry the objects, surfaces, and air around the work area.

Answer 5

Where does the energy come from?

When you pushed the two like charges together, you increased their electrical potential energy, which is converted to kinetic energy when you let them go.