Laws Newton Kepler
Law of Inertia
1st Newton’s first law states
that if a body is at rest or
moving at a constant speed
in a straight line, it will
remain at rest or keep
moving in a straight line at
constant speed unless it is
acted upon by a force. In
fact, in classical Newtonian
mechanics, there is no
important distinction
between rest and uniform
motion in a straight line; they
may be regarded as the same
state of motion seen by
different observers, one
moving at the
same velocity as the particle
and the other moving at
constant velocity with
respect to the particle.
This postulate is known as
the law of inertia.
Law of Acceleration F=a
2nd Newton’s second law is
quantitative description of the
a
changes that a force can produce
on the motion of a body. It states
that the time rate of change of
the momentum of a body is equal
in both magnitude and direction
to the force imposed on it. The
momentum of a body is equal to
the product of its mass and its
velocity. Momentum,
like velocity, is a vector quantity,
having both magnitude and
direction. A force applied to a
body can change the magnitude
of the momentum or its direction
or both. Newton’s second law is
one of the most important in all
of physics. For a body whose
mass m is constant, it can be
written in the form F = ma,
where F (force)
and a (acceleration) are both
vector quantities. If a body has a
net force acting on it, it
is accelerated in accordance
with the equation. Conversely, if
a body is not accelerated, there
is no net force acting on it.
3rd
