Chapter 8 Forces Flashcards
Gravity
The force that keeps us on the ground
Contact force
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
Forces with magnets
Electrostatic forces
Forces about electricity
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 temporary magnet is a magnet that stays magnetized only for a relatively short period of time.
Repulsion
The magnet pushes the other magnet away from it
Magnetic field
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
Frictions
a force that acts against the movement of an object. It occurs between any surfaces that are touching and trying to move past each other
Lubricants
substance with large particles that can slide easily over each other. Lubricants are used between surfaces that rub against each other to reduce wear and increase motion between the surfaces
Traction
a type of friction used to assist movement
Buoyancy
a force which keeps objects floating
Surface tension
the ‘firmness’ of the surface of a liquid created by the attraction between particles at the surface. The surface acts like an elastic skin
