Transcript Newton’s Second Law (part 1)

Newton’s Second Law (part 1)
Forces
• There are 4 basic forces in the world:
• Electromagnetic (ex: makes the sun work)
• Gravitational (ex: tells how all things
physically interact)
• Strong Force
• Weak Force (these two hold atoms together)
Motion
All movement in the universe follows a
set of laws.
2 kinds of motion:
Uniform
Acceleration
(change in motion)
stand
still
rocket
in deep
space
book on
desk
move in
a
straight
line
spee
d up
slow
down
change
directio
n
Newton’s Law
#1
• A body continues at
rest or in uniform
motion unless an
outside force acts on
it
http://media.collegepublisher.com/media/paper889/stills/8tax12b5.jpg
http://farm1.static.flickr.com/87/242834153_3817604b0c.jpg?v=0
Basic Ideas:
this rock has
a lot of
inertia...
or it would
be moving.
•Inertia: “the tendency
of objects to keep doing
what they’re doing”
http://www.allstar.fiu.edu/aero/images/forces.gif
•Force: something that
compels objects to
change their state of
motion
the plane experiences
all these forces to keep it in flight
Seat belts:
•A seat belt exerts a
force on you. No seat
belt allows your inertia
to keep carrying you
through the
windshield, to infinity,
and beyond.
you
(inertia)
car
(inertia)
wall
(applies force,
stops car)
http://www.nordinho.net/vbull/attachments/other-cool-games/8811d1134736413-crash-test-dummy-olympics-crash-test.jpg