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Lottery #3
WarmUp
• The size of the gravitational force between two objects depends on their ____.– A. frictional forces– B. inertia
C. masses and the distance between them speed and direction
WarmUpScivid
Lottery(20 dollar give away)Staple PostersGravity Poster
Mythbusters: Bullet Motion
WarmUpScivid
Lottery(20 dollar give away)Staple PostersGravity Poster
Mythbusters: Bullet Motion
Physical Science Lottery #3Gravity PosterGravity Side +10Projectile Motion side +10
Newtons 2nd Law Poster
Left Side: Notes +10
Right: Math +10
Newtons 3rd Law and Momentum PosterThird Law side +10Momentum side +10
________/__20 pts_
____ /__20_
Back SideCar Crash Lesson Data Table
Force Plate Jump Game
Newton’s First LawInertia Notes on the Left side +10
_____/ 20 pts
Car Crash Physic Movie Facts _____/10 pts
______/__40 pts__
____ /__30_
Newton’s 3 Laws
Newton’s First Law
Short: Law of Inertia
Long: An object in motion stays in motion, an object at rest stays at rest unless acted on by a outside force
Vocab: Force: Push or pull
Example: While in a car you move at the speed of the car(80mph)… when the car stops you continue(80 mph) until you hit another object(windshield)
Example: While in a car you move at the speed of the car(80mph)… when the car stops you continue(80 mph) until you hit another object(windshield)
More examples: 1.Earth’s Rotation and Orbit2.Flying off a bike3.Stuff flying off dash
Newtons First Law DemosNewtons First Law Demos
Marker in a bottle experiment
1.The marker fell in the bottle because its inertia wanted it to fall straight down
Ping Pong ball cannon
1.Ping pong ball continued in its forward motion, can wanted to keep its rest, ping pong ball won.
Egg Spin1.Liquidy egg is not effected when you touch the shell so the egg is harder to start and harder to stop
Mass and Inertia
As the MASS of an object increases so does its INERTIA
List Five objects with a lot of INERTIA:
Net Force
Newton’s Second Law
Short: Force= Mass x Acceleration
Example: How much force will you need to use to push a pop machine that is 1000 kg with an acceleration of 2 meters per second per second
Example: How much force will you need to use to push a pop machine that is 1000 kg with an acceleration of 2 meters per second per secondSimple Rules:
1.The greater the force that is applied to an object the greater
Acceleration it will have
THE HARDER YOU PUSH THE MORE SOMETHING SPEEDS UP, SLOWS DOWN, OR CHANGES DIRECTION
Simple Rules:
1.The greater the force that is applied to an object the greater
Acceleration it will have
THE HARDER YOU PUSH THE MORE SOMETHING SPEEDS UP, SLOWS DOWN, OR CHANGES DIRECTION
F= ma F= ma
A= 2000 N/ 2 kgA= 2000 N/ 2 kg 1000 m/s/s1000 m/s/s
=
If we pushed a box of kleenex ( 2kg) with the same force ( 2000N) then what would our acceleration?If we pushed a box of kleenex ( 2kg) with the same force ( 2000N) then what would our acceleration?
HINT: If not solving for force, force is always on top
Newton’s Second Law Math
F=ma
A= F/m
M=F/a
2. If Force is unchanged, then the greater the Mass of an object the lower the acceleration will be
THE HEAVIER SOMETHING IS THE HARDER IT IS TO MAKE SPEED UP, SLOW DOWN, CHANGE DIRECTION
2. If Force is unchanged, then the greater the Mass of an object the lower the acceleration will be
THE HEAVIER SOMETHING IS THE HARDER IT IS TO MAKE SPEED UP, SLOW DOWN, CHANGE DIRECTION
A= F/M A= F/M =
Draw a situation that describes the two rules
Friction
Friction: This is the force that always opposes motion.
Three Types of FrictionStatic Friction: Friction between two surfaces that are not movingStatic Friction: Friction between two surfaces that are not moving
Rolling Friction: Friction between rolling object and a flat surface(least amount of frictionRolling Friction: Friction between rolling object and a flat surface(least amount of frictionSliding Friction: Friction between flat surfaces where there is some movement but force must be constantly appliedSliding Friction: Friction between flat surfaces where there is some movement but force must be constantly applied
Newton’s Second Law Description
F = 1000 x 2 F = 1000 x 2 2000 N=
GravityGravity: A force of attraction between two objectsGravity: A force of attraction between two objects
Big objects attract little objects to them:Big objects attract little objects to them: Time Speed (m/s) Acceleration Distance
covered
1 s 10 10 102 s 20 10 303 s 30 10 604 s 40 10 1005s 50 10 1506s 56 10 206
The average skydiver hits his terminal velocity at a speed of 56 m/s
The average skydiver hits his terminal velocity at a speed of 56 m/s
Terminal velocity: highest velocity a falling object can reach due toforce air resistance = force gravity
Terminal velocity: highest velocity a falling object can reach due toforce air resistance = force gravity
When an object is in free fall it is no longer accelerating
ALL OBJECTS FALL AT THE SAME SPEED TOWARDS THE EARTH BUT SOME ARE AFFECTED MORE BY AIR.
ALL OBJECTS FALL AT THE SAME SPEED TOWARDS THE EARTH BUT SOME ARE AFFECTED MORE BY AIR.
Why does a feather fall at a different speed than a hammer on earth but not on the moon?
There is no air resistance on the moon!
Projectile Motion
Weight: The effect of gravity on an objectWeight: The effect of gravity on an objectWeight = Mass x gravityWeight = Mass x gravityWeight: The effect of gravity on an objectWeight: The effect of gravity on an objectWeight = Mass x gravityWeight = Mass x gravity
Mass Weight
Belongs to an object( always the same)
Changes depending on the planet or moon
What if one object object is shot horizontally and another is dropped?What if one object object is shot horizontally and another is dropped?
The only force acting on either ball is GRAVITY so they fall at the same rate and hit the ground at the same time
The only force acting on either ball is GRAVITY so they fall at the same rate and hit the ground at the same time
Strength of Gravity is determined by Mass and distance
Car Crash Lesson Data Table
Person Mass (kg)
Mass= Weight/ 9.8
Initial Force
This is also the weight
Mass x gravity
Final Force(Final F –Initial F)
Jumping Force Jumping Acceleration(m/s/s)
A= Force/Mass
FORCE PLATE JUMP GAME