Magnetism And Electromagnetism Flashcards
Where are the forces the strongest on a magnet?
At the poles
What happens when you place like poles of a magnet next to each other?
They repel
what happens when you place unlike poles on a magnet next to each other?
They attract
Which materials are magnetic?
Iron,steel,cobalt,nickel
What is the direction of the magnetic field?
North to south
What is a permanent magnet?
A material that produces its own magnetic field
What is an induced magnet?
A material that becomes magnetic when in a magnetic field
What happens to the strength of a magnetic field when the distance from the magnet is increased?
It becomes weaker
What happens when a current flows through a conducting wire?
A magnetic field is produced around the wire
What affects the strength of the magnetic field around a wire?
Size of current, distance from wire
What does shaping a wire to form a solenoid do to the magnetic field?
Increases the strength of the magnetic field
What is an electromagnet?
A solenoid with an iron core
How do you change strength of an electromagnet?
Increasing the number of coils,inserting an iron core, increasing the current
What is the motor effect?
When a conductor placed in a magnetic field experiences a force
What causes the motor effect?
Interaction between magnetic fields (wire and permanent magnet)
What does Flemings left hand rule show?
Direction of force (thumb), magnetic field (first finger), current (middle finger)
What is the equation linking force,magnetic flux density,current and length?
Force = magnetic flux density x current x length
What do you call a coil of wire carrying a current in a magnetic field that has a tendency to rotate?
An electric motor
