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laughs

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Newton's second law of motion

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let's learn about Newton's second law of

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motion there is an equation that goes

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along with this law

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this equation states that Force equals

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mass times acceleration

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that means the mass of an object and the

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force pushing it determine how fast that

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object will move

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let's take another look at Newton's

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equations so we can break it down

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the F in the equation stands for force

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have you ever thrown a football pushed a

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swing

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pulled a wagon

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squeezed a sponge or Twisted the cap off

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a soda bottle

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if you've done any of these things then

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you have applied force to an object

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pushing pulling twisting and squeezing

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are all ways to apply Force to something

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sometimes people apply Force to things

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and other times different objects apply

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Force to each other

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but whenever a force is applied there

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are always two things interacting

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now let's define the word mass in

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Newton's equation

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mass is the amount of matter or stuff

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inside everything even us

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all objects are made up of different

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amounts of matter that means their mass

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is different too

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for example an elephant has way more

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mass than a cricket on the other hand a

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large balloon has much less mass than a

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small rock even though the balloon is a

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lot bigger than the Rock The Rock has

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more mass because it is made up of more

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matter

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here's another example

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a softball is about the same size as a

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cannonball

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but the softball is lighter or has less

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mass than the Cannonball

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that's because the matter or stuff

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inside each ball is different and what

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they are made up of affects how much

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mass they have

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a cannonball is made from lead which has

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a lot of mass

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while a softball is made from Cork which

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has a lot less mass than lead

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see if you can answer these questions

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which has more mass

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a golf ball or a ping-pong ball

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did you say golf ball you're right how

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about a bowling ball or a basketball

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if you said bowling ball you're right

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again

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let's move on to the last part of

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Newton's equation

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celebration acceleration means a change

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in speed or direction

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if you step on the gas pedal of a car it

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moves

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when you pedal a bike it does the same

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thing

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if you go off a ramp on your skateboard

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you accelerate

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now that you know the definitions of

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force mass and acceleration

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let's see how these things work together

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in Newton's second law of motion

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take a look at this baseball pitcher

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he can throw a baseball very fast

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if that same picture was given a

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cannonball to throw

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do you think he'd be able to throw it as

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fast or as far as the baseball

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the answer is no do you know why

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if you said it's because the Cannonball

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has a lot more mass than the baseball

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you are absolutely right

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but it also has to do with Force

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because the Cannonball has more mass it

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requires a lot more Force to make it

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move or accelerate like the force from a

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cannon

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one more thing that is important to know

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about forces

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they are either balanced or unbalanced

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look at these kids playing tug of war

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did you notice how neither side is

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moving even though all the kids are

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pulling very hard that's because the

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forces are balanced that means that the

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forces on both sides of the Rope equal

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each other

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so neither side accelerates or moves but

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let's see what happens if we put more

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mass on one of the sides

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what do you think will happen now

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the forces are now unbalanced

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and because they're unbalanced the side

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with more force is causing the Rope to

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move or accelerate in that direction

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Newton's second law is all around us

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like in our example of the game of tug

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of war

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throwing a baseball or a cannonball

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and pulling a wagon with different

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amounts of mass

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take a look around and see if you can

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find any other examples of Newton's

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Second Law hope you had fun learning

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with us visit us at learnbrite.org

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for thousands of free resources and

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