Chapter 8 Forces Flashcards
Gravity
he force of attraction that exists between any two bodies in the universe that have mass. The gravity at the Earth’s surface is the pull on objects near its surface towards the centre of the Earth
Contact forces
a force that acts only between objects that are touching
Non-contact force
a force that acts between objects even though the objects are not touching
Magnetic forces
the force (a push or pull) that acts between magnets (including the Earth) and magnetic objects
Electrostatic forces
a non-contact force of electric charges at rest. We experience electrostatic forces when we pull off a jumper and our hair stands on end
Force
(noun) a push, pull or twist. Forces are measured in newtons (N). (verb) to push, pull or twist
Permanent magnets
A magnet that retains its magnetic effect for many years
Temporary magnets
A magnet that stays magnetic only while it touches a permanent magnet, or one that is magnetic for a very short time
Repulsion
An opposing force
Magnetic Force
A map of lines showing the size and direction of a magnetic force. The size of the force is shown by how close together the lines are. The direction at any point is given by the direction in which the north pole of a magnet would face
Atoms
a very small particle that makes up all things. Atoms have the same properties as the objects they make up
Protons
tiny, but heavy, particle found in the nucleus of an atom. Protons have a positive electrical charge
Neutrons
tiny, but heavy, particles found in the nucleus of an atom. Neutrons have no electrical charge
Insulators
materials that do not allow electric charge to flow through them
Conductors
materials that allow electric charge to flow through them
