IPC. Newton’s 1st Law of Motion Newton’s 1st Law of Motion – Objects in motion will stay in...

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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.