Elastic collision

The moving skate board has more momentum than the stationary train because since the train is not moving its velocity is going to be 0m/s and everything multiplied by 0 is going to be 0, so the train's momentun is 0kgm/s. And the skate board has mass and it also has velocity the skate board is going to have more momentum than the train.

Elastic vs. Inelastic Collision

The difference between Elastic Collision and Inelastic Collision is that when elastic collision happens the two objects will bounce off each other and when inelastic collision happens the objects sill stick together.  An example of inelastic collision is when you roll a marble towards another marble because the marbles are going to keep moving together and at the same speed. And an example of elastic collision is when something small tries to push something big.

Work & Power

   The difference between work and power is that in order to have work you need Force and Distance and in order to have power you need to have work. The power something has depends on the work and the time it takes to do it. If you do a work at .6 seconds and the same work at 20sec. The work done at 6 seconds has more power because it was done faster.a

Mass and Newto's first law

• A bowling ball and a golf ball- A bowling ball has more mass than a golf ball and since it has more mas it has more inertia therefore it will be harder to move so it will need more force than the golf ball.

• A ballom and a rock- The rock has more mass than the ballom because even though the ballom is bigger the rock weights more so the rock has more inertia than the ballom this is why you can move a ballom very easily and it is harder to move a rock.

• If you try to push a car no matter how many times you try you wont do it because it has a lot of mass which means it has more inertia and also because an object that is at rest has to stay at rest unless is acter by another force.

Inertia Investigation

• It is harder to move a big vehicle, like a bus than a smaller vehicle, like a motocycle because tie bigger object has more mass, and the more mas it has the more inertia.

• When a baseball is thrown it will continue to move foward until is acted upon by gravity. Because if an object is moving it will keep moving until its stoped by an unbalanced force.

• Another example of inertia is if you throw a ball off a hill the ball will continue to move until an object or anither force stops it.

Mu- Friction

Friction is a force that acts on an opisite direcrion to movement. Friction happens because without it we couldn't be able to do anything. Something that will have a bigger value of mu with your shoes will be a floor that is smoth because it is easier to walk and it will make more friction.

Free body diagram

    The object I chose was a person I  couldn't put the picture. The car has a net force of 0n because it has a balanced force. This means that if The person has a gravitational force of 20n the normal force will be 20n because the same force that is pulling it to the center of the earth is also pushing it off the ground.


   An object that has an Unbalanced force is an egg falling off a tree. This object is unbalanced because there is no force that is pushing it up so there is not an normal force the only force that it has is gravitational force because its going doen to the center of the earth until something stops it.