Force
example
Say like your in a car and going in a pool you cant open the door half way because the forces of the water is pushing the door shut but when you go all the way down you can because the car door and the water is equal.
Push
Push is when you push someone or push a button it involves fingers and hands pushing someone involves strength Pushing is hard to learn when your little but when you get older its not so bad when you push it it rolls away
Pull
It is when you Shove something or someone it will come towards you if you pull it hard it will come too you fast if its slow it will come too you slow
friction
when you walk the friction moves you forwards so u can go fast when you walk
gravity
Gravity is on the centre of earth so when we walk we wont float if we didn't have gravity we wouldn't know how to learn we would learn to going space and die
air Resistance
when the marble goes town the tube the air will make it Go down and go on the next thing
potential energy
Its when the potential makes the marble stay where it is so it doesn't move when you don't release it it stays on the spot
Kinetic energy
When you release the marble the kinetic makes the marble roll on the spiral thing and makes it go faster
Balanced force
Balanced force is where the object is even it it wasn't even the weight wouldn't be even and one would go higher then the other one
Unbalanced force 
When the object goes the unbalanced force makes the ball go up and down like its jumping and when it goes down the connectors it will jump because the unbalanced force isn't balanced ed with the ball .
accelerate
say the ball is roiling the ball will start getting faster that why the accelerate is making it go fast then it will slow down because it will go on another track .
motion
the motion moves the marble to go and do the work for you it wont stop moving until the motion and all the forces stop on it .
