Be careful when applying Newton's laws, always check if the forces are
the same type and what body they are acting on as it will determine
whether to use the 1st or 3rd law in your answer!
1) Every object
persists in a state of
rest or uniform motion
unless compelled to
change that state by
forces acting on it
EXAMPLE: an object on a table won't go
anywhere as the forces on it are balanced
reaction(R)(force of table pushing object
up)=weight(mg) (force of gravity pulling oblect
down
2) Acceleration is proporional to force
Resultant force(N)=
mass(kg)xacceleration(m/s2)
F=mxa
more force= more acceleration
( for a certain mass)
more mass = less acceleration
(for a given force)
3) For every action
there is an equal and
opposite reaction
REMEMBER: forces are the
same size and the same
type!
Forces act on different bodies
and act in the opposite direction