magnetism and electromagnetism Flashcards
whats a magnet
an object that can attract other objects containing iron, cobalt or nickel
what are ferromagnetic objects
magnetic objects made of iron, cobalt, or nickel
whats a magnetic field
the area of space in which the magnetic force of a magnet can act on another magnet
do the field lines cross
no
which type of magnetic poles attract and which type repels
opposite magnetic poles= attract
like magnetic poles= repel
what is the north pole of a compass
the end of the compass that naturally seeks the Earth’s magnetic south pole near the geographic north pole
what is the electromagnetic force
the force generated by an electromagnetic field
what do things with an electric current create
an electromagnetic field (ex. speakers, motors, fans)
what’s electromagnetism
describes all phenomena resulting from the interaction between electricity and magnetism
how do u make a stronger electromagnet (3)
- more power
- more wraps
- use iron core
what’s the right hand rule for a live wire
1) grasp the wire with the thumb pointing in the direction of the current flow (towards negative)
2) the curled fingers point in the direction of the magnetic field
what’s a solenoid
long, thin loop of the wire which produces a magnetic field when an electric current is passed through it
what’s the right hand rule for a solenoid
1) fingers follow current (towards negative)
2) thumb points north
what are the factors affecting resistance (4)
- substance: type of conductor (good=metal, poor= nonmetal)
- length: the longer the wire the greater resistance
- diameter: smaller diameter resists flow more than a larger diameter wire
- temperature: warm wire resists more than a cold one
