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 WarmUp Scivid Lottery(20 dollar give away) Staple Posters Gravity Poster Mythbusters: Bullet Motion WarmUp Scivid Lottery(20 dollar give away) Staple Posters Gravity Poster Mythbusters: Bullet Motion

Physical Science Lottery #3 Gravity Poster Gravity Side +10 Projectile Motion side +10 Newtons 2 nd Law Poster Left Side: Notes +10 Right: Math +10 Newtons 3 rd Law and Momentum Poster Third Law side +10 Momentum side +10 ________/__20 pts_ ____ /__20_

Back Side Car Crash Lesson Data Table Force Plate Jump Game Newton’s First Law Inertia 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) More examples: 1.Earth’s Rotation and Orbit 2.Flying off a bikeFlying off a bike 3.Stuff flying off dash Newtons First Law Demos Newtons 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 Spin 1.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 Simple Rules: 1.The greater the f orce that is applied to an object the greater A cceleration it will have THE HARDER YOU PUSH THE MORE SOMETHING SPEEDS UP, SLOWS DOWN, OR CHANGES DIRECTION Simple Rules: 1.The greater the f orce that is applied to an object the greater A cceleration it will have THE HARDER YOU PUSH THE MORE SOMETHING SPEEDS UP, SLOWS DOWN, OR CHANGES DIRECTION F= ma A= 2000 N/ 2 kg 1000 m/s/s = 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 M ass of an object the lower the a cceleration 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 M ass of an object the lower the a cceleration will be THE HEAVIER SOMETHING IS THE HARDER IT IS TO MAKE SPEED UP, SLOW DOWN, CHANGE DIRECTION A= F/M = Draw a situation that describes the two rules Friction Friction: This is the force that always opposes motion. Three Types of Friction Static Friction: Friction between two surfaces that are not moving Rolling Friction: Friction between rolling object and a flat surface(least amount of friction Sliding Friction: Friction between flat surfaces where there is some movement but force must be constantly applied Newton’s Second Law Description F = 1000 x N =

Gravity Gravity: A force of attraction between two objects Big objects Big objects attract little objects to them: Big objects Big objects attract little objects to them: TimeSpeed (m/s)AccelerationDistance covered 1 s 10 2 s s s s s The average skydiver hits his terminal velocity at a speed of 56 m/sskydiver The average skydiver hits his terminal velocity at a speed of 56 m/sskydiver Terminal velocity: highest velocity a falling object can reach due to force air resistance = force gravity Terminal velocity: highest velocity a falling object can reach due to force 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. 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:Weight: The effect of gravity on an object Weight: Weight = Mass x gravity Weight:Weight: The effect of gravity on an object Weight: Weight = Mass x gravity MassWeight 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? 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

PersonMass (kg) Mass= Weight/ 9.8 Initial Force This is also the weight Mass x gravity Final Force(Final F –Initial F) Jumping ForceJumping Acceleration (m/s/s) A= Force/Mass FORCE PLATE JUMP GAME