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IPC
Newton’s 1st Law of Motion
• Newton’s 1st Law of Motion – Objects in
motion will stay in motion and objects at rest
will stay at rest…unless a force acts on them.
The ball will stay at rest (not move) unless the
dog moves it.
Newton’s Second Law of Motion
• Newton’s Second Law of Motion - "F = ma:
the net force on an object is equal to the mass
of the object multiplied by its acceleration.
You bunt – the ball doesn’t go far. You swing
hard (more force), the object accelerates
faster.
Newtons Third Law of Motion
• Newton’s Third Law of Motion - To every
force or action, there is always an equal and
opposite reaction.
• The cannon has a backward kick when it is
fired.."
Question
• What makes an object difficult to stop?
Momentum
Momentum
Momentum
Question
• A ball of mass 2 kg. is moving with a speed of
4 m/s. What is its momentum?
Answer
A ball of mass 2 kg. is moving with a speed of 4
m/s. What is its momentum
Momentum = (mass)(velocity)
= (2 kg)(4 m/s)
= 8 kg m/s
Mass
• More mass means more momentum
• Twice the mass means twice the momentum.
Law of Conservation of Momentum
• For a collision occurring between object 1 and
object 2 in an isolated system, the total
momentum of the two objects before the
collision is equal to the total momentum of
the two objects after the collision MV = MV
Centripetal Force
• Centripetal Force- force directed towards the
center of the circle for an object moving in a
circular motion.
Centripetal Acceleration
• Centripetal Acceleration – Acceleration
toward the center of a curved or circular path.
Friction
• Friction - when 2 objects rub together. It
generates heat. Example (rub your hands
together)
Sliding Friction
• Sliding Friction- is when two objects are
rubbing against each other. Putting a book flat
on a desk and moving it around is an
example of sliding friction.
• Have you ever pushed a box before.
Rolling Friction
• Rolling friction- is the resistance that occurs
when a round object such as a train rolling on
a track or a ball rolling on a surface.
Air Resistance
• Air resistance – Like turbulence…….objects
slowing down in the wind. Running into the
wind.
Weight
• Weight – Changes with gravity. It Is different
on every planet.
Mass
• Mass – Always remains the same. Triple Beam
balance can measure mass.
Law of Gravitation
• Law of Gravitation - states that any two
objects exert a gravitational force of attraction
on each other. The moon’s gravitational force
causes tides.
Gravity Constant
• Gravitational Acceleration (gravity constant)
– 9.8 m/s2 (If you get thrown out of a plane,
you will accelerate to the eart at 9 m/s2)
Projectiles
• Projectiles – Objects that are launched and fly
through the air (bullets, missiles)
Static Fricton
• Static friction - Static friction is a force
between two objects that are not moving
relative to each other.