Download Chapter 9 Study Guide

6th Grade Chapter 9 Test Study Guide
Materials through which charges can flow easily are called conductors
Materials through which charges cannot flow easily are called insulators
The buildup of charges on an object is static electricity
A complete, unbroken path through which electric charges can flow is called electric circuit
The loss of static electricity as electric charges transfer from one object to another, such as when
lightening strikes an object, is called static discharge
The transfer of electrons from one uncharged object to another uncharged object by rubbing the two together
is called friction
The transfer of electrons from one object to another by direct contact is called conduction
The continuous flow of electrical charges through a material is called electric current
The relationship between electricity and magnetism is called electromagnetism
A device that measures current is called galvanometer.
A coil of wire with a current is called a solenoid.
A coil of wire with a ferromagnetic core and with a current is called an electromagnet.
A device that converts mechanical energy into electrical energy is called a generator.
The area of magnetic force around a magnet is called a magnetic field.
A current with charges that flow in one direction is called direct current.
The type of current that is constantly reversing is called alternating current (AC).
*The electric current in the circuits in homes, schools, and office building is alternating current.
Transformers
A device that changes the voltage of current is called a transformer.
A transformer that increases voltage is a step-up transformer.
The step-down transformer shown below decreases voltage.
Conductors & Insulators
Examples of good conductor of electric current: transition metals like silver and copper
Examples of poor conductors: glass, wood, plastic, rubber
Insulators have a higher resistance to electric current than conductors.
Circuits
Circuits have 3 major parts:
The wires in a circuit represent the “path” of the circuit, a battery represents the “power source,” and the
“load” would be represented by a device such as a lightbulb.
Atoms
The charge on the electron of an atom is negative. The charge on the proton of an atom is positive.
Resistance
As the diameter of a wire increases, resistance decreases.
As the distance from the charged particle increases, the strength of the electric field decreases.
As the length of a wire increases, resistance increases.
As the temperature of most conductors increases, the resistance increases.
The unit of measurement used for resistance is called an ohm.
An electric current produces a magnetic field.
One way to increase the strength of a magnetic field is to increase the current.
To reverse the direction of the magnetic field, you would reverse the direction of the current.
The movement of a conductor through a magnetic field produces a current.
Moving a coil up through a magnetic field will cause the current to flow clockwise.
Moving a coil down through a magnetic field will cause the current to flow counterclockwise.
The unit of measure used for current is called an ampere.