Transcript How does matter become charged?

How does matter become charged?
• Most kinds of atoms have three kinds of particles.
Particles can have a positive charge, negative
charge, or no charge.
• Static electricity happens when positive and
negative charges between two objects are close to
each other are unbalanced.
• Negative particles gather at the BOTTOM of a
cloud before energy is released as lightning.
How Charged Objects Behave
• Objects with opposite charges will attract
each other.
• Objects with the same charge will repel
each other.
• An electric force is the push or pull
between objects that have different
charges.
How do electric charges flow?
• An electric charge in motion is an electric
current.
• In order for an electric current to flow, a circuit
must be closed.
• An insulator, such as plastic, rubber, glass, and
dry wood, are materials through which charges
CANNOT travel easily.
• A conductor, such as copper and silver, are
materials through which charges CAN travel
easily.
Types of Circuits
• In a series circuit, an electric current
travels in one path, a single loop.
– One missing bulb opens the circuit
and other bulbs WILL NOT light.
• In a parallel circuit, the current has more
than one path it can follow as it travels
through the entire circuit.
– A missing bulb does not open the circuit and
the other bulbs WILL light.
Types of Circuits
• Series Circuit
• Parallel Circuit
What are magnetic fields?
• A magnet is surrounded by an invisible
magnetic field.
• All magnets have two poles with opposite
charges.
• A magnetic field is strongest at both poles.
How Compasses Work
• Earth is surrounded by a huge magnetic
field.
• A compass needle reacts to Earth’s
magnetic poles. The needle of the compass
aligns north-south so that one end points to
Earth’s magnetic north pole and the other
to the magnetic south pole.
How is electricity transformed to
magnetism?
• An electromagnet is a coil of wire wrapped
around an iron core.
• The strength of an electromagnet can be changed
by using more turns in the metal coil.
• Electrical energy is produced when a coiled wire
is spun around a magnet.
• In a door bell, electromagnets help convert
ELECTRIC ENERGY to MAGNETIC ENERGY
to MECHANICAL ENERGY.
How is magnetism transformed
to electricity?
• Magnetism can be used to generate
electricity.
• Most electricity comes from generators.
• Michael Faraday shared his investigation
with other scientists when he discovered
changing a magnetic field caused an
electric current in a wire.
Essay Question
• Explain what happens to a magnet’s poles
if a magnet is broken into two parts. What
poles will seek each other on the two
magnet parts? What poles will repel each
other?