Chapter 10

Definition: a form of energy that is the result of the interaction of charged particles, such as electrons or protons

Extra Info: Electricity can be moving (i.e. an electric current, which is the flow of electrons) or still (i.e. static electricity). Electricity can be produced through different methods by humans, such as hydroelectricity, nuclear energy, and solar energy.

• Related Terms:
• -Static Electricity (unmoving electricity)
• -Electric Current (the flow of electrons)
• -Electrons (a charged particle that can create electricity)
• -Protons (a charged particle that can create electricity)

Definition: an electric charge that usually stays on the surface of an object, and stays more or less unmoving without interference (e.g. from other electric fields)

Extra Info: Static electricity can be transferred through several methods such as, charging by friction, charging by contact, and charging by induction.

• Example: static electricity on hair, static electricity on a comb 

• Related Terms:
• -Electricity (static electricity falls under this term)
• -Electric Current (static electricity's opposite, the flow of electricity)
• -Electroscope (can be used to determine the type of charge (static) on an object)
• -Charging by Contact (a process of transferring electrons)
• -Induced Charge Separation (can occur to static charges)

Definition: a process in which objects (made from different materials) are rubbed together, producing a net static charge on each (e.g. positive, negative)

Extra Info: Only electrons are transferred during this process. There are other ways to transfer electrons and/or change net charges on objects, such as charging by contact, or induced charge separation.

• Example: Rubbing a hand on a balloon (the hand has a weaker hold on electrons were transferred to the balloon)

• Related Terms:
• -Charging by Contact
• -Induced Charge Separation

Definition: a list of materials arranged by their ability to hold on to electrons

Extra Info: The higher up something is on the electrostatic series, the weaker its hold on electrons, so the lower on the list, the stronger its hold.

• Example: Glass                  (Weak)
•                Fur                           |
•                Rubber Balloon        |
•                Foam                       /
•                Ebonite                (Strong)

• Related Terms:
• -Electrons (the stronger the hold on these, the lower a material is on the Electrostatic series)

Definition: a material that does not allow electrons to move easily between atoms

Extra Info: It does not depend where a material is on the electrostatic series for whether or not it is an insulator or not (e.g. glass is an insulator that is high on the list, while rubber is an insulator that is low on the list).

Example: Glass, pure water, plastic, and rubber are insulators.

• Related Terms:
• -Conductor (opposite of insulators)
• -Semiconductor (between conductors and insulators)

Definition: a material that allows electrons to move easily between atoms

Extra Info: The placement of a material on the Electrostatic Series does not determine whether or not it is a conductor or not (since metals are not on the Electrostatic Series, and non-metals usually do not conduct electricity very well (except for the rare ones, such as silicon, which would be considered a semiconductor)).

Examples: Copper, aluminum, mercury (all metals) are conductors.

• Related Terms:
• -Insulator (opposite of conductors)
• -Semiconductor (between conductors and insulators)

Definition: a material in which electrons can move fairly well between atoms

Extra Info: Semiconductors can be non-metal conductors, since non-metals can be considered worse at conducting than metals, and thus put in the category of semiconductor.

Example: Silicon, and germanium are semiconductors.

• Related Terms:
• -Conductors (metals, can conductor better than semiconductors)
• -Insulators (do not allow electrons to move easily between atoms, opposite of conductor)

Definition: an object that can supply a large number of electrons to, or can remove a large number of electrons from, a charged object, to keep the object neutral

• Extra Info: Many plugs for electronics have a third prong at the bottom. This prong is the ground.

Examples: The earth.

• Related Terms:
• -Electrons (they are transferred to and from the ground)

Definition: a device that detects the presence of an electric charge

Extra Info: There are different kinds of electroscopes (e.g. metal-leaf electroscopes, and pith ball electroscopes).

• Example: Metal-leaf electroscope, and pith ball electroscopes are both electroscopes.
• Metal-Leaf Electroscope (is working because of Induced Charge Separation):

• Related Terms:
• -Static Charge (Static Electricity) (the Electroscope will show if a charge, negative or positive, is present)
• -Induced Charge Separation

Definition: generating a charge on a neutral object by touching it with a charged object

Extra Info: This process can never cause the previously charged object to become the opposite charge (e.g. if a positively charged rod touched a ball, the rod would not lose so many electrons that it becomes positive; at the most it would become neutral). Also, the neutral object will become the same charge as the charged object (e.g. negatively charged rod, neutral ball, after touching; the ball will be negatively charged).

• Example: A positive rod touches a neutral ball, which transfers electrons from the ball to the rod, and the ball is now positively charged:

• Related Terms:
• -Charging by Friction
• -Induced Charge Separation

Definition: laws that describe how two objects interact electrically when both or one are charged

Extra Info: Like charges repel, opposite charges attract, and neutral objects are attracted to charged objects.

• Example:

• Related Terms:
• -Electrons (more of these than protons create a negative charge, equal amounts are neutral)
• -Protons (more of these than electrons create a positive charge, equal amounts are neutral)

• Definition: a property of the space around a charged object, where the effect of its charge can be felt by other objects
• Example: a positively charged ball will move towards a negatively charged rod

Definition: the movement of electrons in a substance, due to the electric field of a nearby charged object, with no direct contact between the charged object and the substance

• Example: If a negatively charged rod is held near a neutral ball, the electrons in the ball will move as far as they can from the rod because they are repelling away from the excess electrons in the rod. This causes the side closest to the rod to become positively charged, while the side farthest becomes negatively charged:

• Related Terms:
• -Charging by Friction
• -Charging by Contact
• -Electric Field

Definition: a charged atom/group of atoms (negatively charged or positively charged)

• Related Terms:
• -Electrons
• -Protons

Definition: a metal sphere or point that is attached to the highest part of a building and connected to the ground

• Extra Info: Lightning rods are used to protect buildings, such as skyscrapers or farmhouses.
• Related Terms:
• -Ground (the rod is attached to the ground so the electrons have a safe place to go)

• Definition: a type of cleaner that removes the unwanted particles and liquid droplets from a flow of gas
• Extra Info: It can be very effective for reducing pollution from smokestacks, such as the ones in a Hamilton, Ontario steel plant.

Definition: a device that accumulates very large charges

• Example:

• Related Terms:
• -Static Electricity

Definition: a small device that detects and measures exposure to radiation

Extra Info: Astronauts and people who work with radioactive materials are the type of people who would wear a radiation dosimeter. There are different types of radiation dosimeters.

Example: Metal-leaf electroscope like radiation dosimeter.