What is Electric Charge?

Electric Charges

Electric charge is a basic property of matter. Recall that matter is made up of atoms, and atoms are composed of smaller subatomic particles called:

______

The protons are ______charged and located in the ______, along with the neutrons, which are ______charged. The ______are ______charged and orbit quickly around the nucleus.

By adding up all the charges that an atom has, we can determine the atom’s overall net charge. For example, when an atom has an equal number of protons and electrons, the charge is ______.

When the number of electrons and protons are not equal, the atom will have either a positive or negative charge. An atom with a charge is called an ion.

Draw an atom of helium (He).

Static Charge

Most of the time, objects are electrically ______. However, electrons can be transferred from one object to another. If a neutral object gains electrons its overall charge will be ______and if a neutral object loses electrons its overall charge will be ______.

An object’s excess of positive or negative charge is called ______.

Objects can be classified as either a ______, where the electrons are held loosely and therefore move ______. Examples of conductors are metals (silver, copper, aluminium). An ______is a material that ______allow the electrons to move easily. Example: non metals (glass, rubber, plastics).

Electric Force

All charged materials or objects exert a force called ______.

  1. Materials with ______or unlike static charges will ______one another, or pull each other closer.
  2. Materials with ______static charges, will ______each other, or ______each other away.

Why do you think an atom is held together?

Remember that charged atoms ______have to ______each other for electric force to act between them. Electric force can act over a ______. When this happens, the space around the charged object is called an ______.

The size of the electric force between two charged materials depends on:

  1. The ______of the ______charges. (Greater charges = Greater force)
  2. The ______between the charges. (As the distance ______, the force decreases)

How can objects become charged?

  1. Charging by ______– When two objects are ______together, electrons are transferred from one object to the other. Ex. Static Cling. When two neutral objects are charged by ______, the objects have ______charges because no new charges are being created. (Electrons are simply moving from one object to the other.)
  1. Charging by ______– Neutral objects can become charged when they come in ______with an already charged object. When a charged object ______a neutral object, the electrons are______to the neutral object. Example: rubber rod to a pile of confetti.
  1. Charging by ______– Contact is not always ______for objects to become charged. When a charged object is brought ______to a neutral conductor, electrons in the conductor move to new positions, and the conductor becomes temporarily charged. ______causes an object to have areas of both ______and ______charge. Example:

Static Discharge

A charged object will lose its static charge ______, and return to its ______state. The loss of static charge is called ______.

Static discharge can also happen quickly through a process called ______. Connecting a charged object to a much larger conducting material is called grounding. Have you ever received a shock when you touched a doorknob after walking across a carpeted room? Do you know why that happened? When you walked across the carpet, ______rub off the carpet onto the bottom of your socks. This gives you a ______charge. When you touch a doorknob, you are grounded. The ______rapidly jump from your hand to the doorknob.