vocab
a device having a designed resistance to the passage of an electric current
as long as a power source is connected
what is an electromagnet creates a magnetic force
What is the force between two electrons?
repulsive
What can iron fillings be used to show?
A magnetic field
Which device is used to measure small electric currents?
What is a generator
machine for converting mechanical energy into electricity
As the voltage of the source powering a electromagnet increases, the magnet force generated by the electromagnet what?
what is increases
What property of a wire increases when its made thinner?
Its resistance
What will the north poles of two magnet do when brought together?
Repel
The two north poles of a magnet when brought together will?
Repel
What is direct current?
an electric current flowing in one direction only
what material does not attract to a magnet
what is copper
What unit of electrical energy is sold by electric companies?
Kilowatt-hour
How many poles do all magnets have?
Two
A dc battery provides?
Potential energy
What is electromagnetism?
a type of physical interaction that occurs between electrically charged particles
The flow of charged particles is called?
a electric current
As more devises are added to the circuit what happens to the current?
It decreases
When a current-carrying wire is wrapped around a iron core, what can it create ?
A magnet
The greater voltage of the battery, the larger the?
What is a electrochemical cell?
a cell capable of either generating electrical energy from chemical reactions or using electrical energy to cause chemical reactions.
Like charges____; and unlike charges_____
repel and attract
How much power does a hair dryer use
1,200 w
What does a transformer between utility wires and your house do?
Decrease voltage
A light bulb transforms electrical energy into?
Heat and light energy