| Question |
Answer |
| Force | push or pull that acts on an object |
| Forces can: | cause an object that is not moving to start moving, stop an object that isn't moving, change the way an object is moving, change the shape of an object (squeezing, stretching, etc) |
| Types of forces | Contact forces, action-at-a-distance forces |
| Contact forces | directly puts a force on an object |
| Types of contact forces | Direct pushes, tension force, friction force, elastic force |
| Action-at-a-distance forces | puts a force on an object without touching it (indirectly) |
| Types of action-at-a-distance forces | gravitational force, magnetic force, electrostatic force |
| Tension force | experienced by a rope or wire when it is pulled at either end (contact force) |
| friction force | slow down or stop a moving object because of the surfaces rubbing together (contact force) |
| elastic force | a spring-like material restoring itself to its normal shape after it has been (contact force) compressed or stretched |
| gravitational force | acts between objects because they have mass (it can be on any 2 objects) (action-at-a-distance force) |
| Magnetic force | pushes or pulls on objects that have iron, nickel, or cobalt in them (action-at-a-distance force) |
| Electrostatic force | pushes or pulls between objects that have extra positive or negative charges on them (action-at-a-distance force) |
| Mass | amount of material in object (measured in g/kg and never changes) |
| weight | amount of gravitational force on object (depends on the mass and where you are--how far away from earth you are) |
| Newton | in metric system, forces are measured in newtons(N) |
| Newtons are named after: | Sir Isaac Newton |
| Force-meters | use a spring or other elastic device that is pushed or pulled |
Ch.18 LTI-MA 509
