Transcript Life Science - Tom R. Chambers

Newton's Laws of Motion are three physical laws that form the
basis for Classic Mechanics.
Understanding Newton's
First Law of Motion
The first law deals with forces and changes in velocity. For
just a moment, let us imagine that you can apply only one
force to an object.
That is, you could choose push the object to the right or
you could choose to push it to the left, but not to the left
and right at the same time, and also not up and to the
right at the same time, and so on.
Understanding Newton's
Second Law of Motion
For every action, there is an equal and opposite reaction.
This law states that if you do place a force on an object, it will accelerate,
change its velocity, and it will change its velocity in the direction of the force.
Firstly,
it accelerates in the direction
you push it.
Secondly,
if you push twice as hard, it
accelerates twice as much.
Thirdly,
if you push on it, it pushes on you.
Newton’s Third Law of Motion
The Third Law states that for every force
there is an equal and opposite force.
For example, if you push on a wall, it
will push back on you as hard as you
are pushing on it.
Every object persists in its state of rest or uniform motion in a
straight line unless it is compelled to change that state by forces
impressed on it.
2) Force is equal to the change in momentum per change in time.
For a constant mass, force equals mass times acceleration.
3) For every action, there is an equal and opposite reaction.
1)
› It is important to note that these three
laws together with his Law of
Gravitation provide a satisfactory basis
for the explanation of motion of
everyday macroscopic objects under
everyday conditions.
› However, when applied to extremely
high speeds or extremely small objects,
Newton's Laws break down; this was
remedied by Albert Einstein's Special
theory of Relativity for high speeds and
by Quantum Mechanics for small
objects.
Who discovered these Laws of Motion?
 Sir Isaac Newton was born on January
4, 1643 at Woolsthorpe Manor in
Woolsthorpe-by- Colsterworth , a hamlet
in the county of Lincolnshire. At the time
of Newton's birth, England had not
adopted the latest papal calendar and
therefore his date of birth was recorded
as Christmas Day, 25 December 1642.
Newton was born prematurely, he was a
small child; three months after his
father’s death.
 He was an English physicist,
mathematician, astronomer, natural
philosopher, alchemist, theologian and one
of the most influential men in human history.
(1643-1727]
Sir Isaac Newton
Mechanics
& Gravitation
In 1679, Newton returned to his work
on mechanics, gravitation and its
effect on the orbits of planets, with
reference to Kepler's Laws of
Planetary Motion.
Newton's reawakening interest in
astronomical matters received
further stimulus by the appearance
of a comet in the winter of
1680/1681.
Newton worked out a proof that the
elliptical form of planetary orbits
would result from a centripetal
force inversely proportional to the
square of the radius vector .
Quote: “We build too many walls and not enough bridges.”
-Isaac Newton
The End