Vocabulary
Define code.
a set of signals that represents letters or words for sending messages
Define core.
in an electromagnet, the material around which a coil of insulated wire is wound
How do you get an object to start moving?
Apply a force.
What is an electromagnet?
a piece of iron that becomes a temporary magnet when electricity flows through an insulated wire wrapped around it
What does it mean if an object is stationary?
it is not moving
Define fuel.
a source of energy when burned
Define heat.
observable evidence of energy
How do you get an object to stop moving?
Apply a force in the opposite direction.
What are the 4 main components (parts) of an electromagnet?
rivet, wire, battery, switch
Give 2 EXAMPLES of changes in motion.
kicking a soccer ball in a different direction, catching a baseball, throwing a football, catching a baseball, etc.
Define collision.
when one object hits another object
Define friction.
a force acting between surfaces passing each other; friction acts to resist motion
What are 2 examples of observable evidence of energy?
heat, light, sound, or motion
Give one example of how to make an electromagnet stronger.
increase the amount of electric current flowing through the wire, add more coils of wire, or wrap thicker wire around the core
What was Oersted's historic discovery?
A compass needle rotated when it was close to a wire that had current flowing through it.
Define potential energy.
energy that matter has because of its position
Define kinetic energy.
energy that matter has because of its motion
What is the most common source of energy used by people?
The sun
Explain how to create an electromagnet.
You have to connect the wire to the battery and the switch. Then, you have to wrap the wire around the rivet enough times to send a significant amount of energy through the rivet to create magnetism.
Give 3 TYPES of changes in motion.
starting, stopping, change in speed, change in direction
Define transfer of energy.
what happens when objects collide and energy is transferred from the object with more energy to the object with less energy
Define telegraph.
a device that uses an electromagnet to send coded messages by closing and opening an electric circuit
How are food, fuel, and batteries all alike?
They are all sources of energy.
How does an electromagnet work?
Current flowing through an insulated wire creates a magnetic field. Winding the wire around an iron core increases the strength of the magnetic field. The strong magnetic field induces magnetism in the iron core, creating an electromagnet while the current flows.
Why did the compass needle rotate when Oersted ran electric current through the thin wire?
The magnetic field around the wire interacted with the magnetic field of the compass needle.