ch#1 forces Flashcards
define force
A force is a push or pull that can change the shape of the object, or change the way that it moves.
Define gravitational force.
gravitational force, is the force that attracts you to Earth.
define upthrust
upthrust is the upward force exerted on an object when it is in a liquid.
how is force measured?
force is measured by a forcemeter, such as a spring balance. force is measured in newtons.
define friction.
friction is the force that slows down moving objects.
how can friction be reduced?
friction can be reduced by using lubrication. eg-biker lubricate their bike chains to reduce friction.
define gravity
Gravity is the force that pulls you down to earth
what does the force of gravity depend on?
1-the mass of the two objects
2-how far apart they are
define air resistance and what it is caused by.
when an object moves through the air, there is a force called air resistance acting upon it.
It is caused by the air particles hitting each other one after another.
how can air resistance be reduced?
air resistance can be reduced by an object being made more streamlined. this means making the tip of an object more rounded so the air particles can move past it faster.
how can air resistance be used?
Air resistance is very useful for slowing things down. EG- a parachute is not streamlined therefore it slows down the air particles and slows down.
why is upthrust caused?
upthrust is caused because of water particles pushing up on an object in liquid.
define plastic.
if something is not Elastic, and does not go back to the original length, we call it plastic.
what does Archimedes’ Principle state?
Archimedes’ Principle states that an object submerged in a fluid experiences an upward buoyant force equal to the weight of the fluid it displaces.
