L1: forces and motion Flashcards
What do we use to measure forces?
newton meter
what is the unit of force?
newtons
what is the other name for the force of gravity?
weight
what is the difference between contact and non contact forces?
you need to make contact for contact forces to work where non contact forces you don’t
What is upthrust?
when water makes things float
what is thrust?
forward push like a car or plane
what is lift?
when things are going upwards like air pushing a plane upwards
what is air resistance?
air slowing things down
What is weight?
gravity pulling things down
What is magnetic?
magnets attracting or repelling
What is reaction?
contact force between surfaces
What is elastic?
an object which can be squashed or stretched and still go back to its original form
what is friction?
when things slow down because to surfaces are rubbing together
do forces have a size and direction?
yes
how can we represent a force?
by drawing and arrow
what does a longer arrow mean when drawing forces?
a bigger force
what does the direction of the arrow show about the force?
the direction of the force
what is a balanced force?
if two forces are equal and opposite, it also means that the resultant force is 0
what happens if the forces are balanced but the objects were already moving?
that means the objects are at a constant speed, if it was still, it means it is still
what is an unbalanced force?
if two forces are unequal and opposite, this also means that the resultant force will be above 0N
what happens when two forces are unbalanced?
the speed of an object will either accelerate, decelerate or change direction
