Moving a marble in a maze using wind force For a school assignment, I have to write a game where you can move a ball through a maze by generating unidirectional wind when the mouse is clicked.
The ball is on a flat surface.
The concept is shown in this video
I am terrible at physics so I have a couple of questions:
1) What is the precise name of the wind force which will move the ball? I have done some research already and I think it has something to do with "drag".
2) I am looking for some formulas to calculate the speed and the movement etc.
3) Are there other factors I have to take into account?
If further information is needed, I will try to provide. The assignment is quite vague though.
Thank you very much in advance
 A: 1) The force is not drag. Drag is a force which opposes your velocity - it is essentially friction with the air. Your force is what I would refer to as an "applied force", like a push or shove. You are applying your breath to push a marble.
2) Your teacher hopefully doesn't expect you to model friction - it is difficult, and the effects are going to be small with a ball. What I would do is use momentum. 
Force (newtons)*Time (seconds) = Impulse. 
Impulse = Change in momentum. 
Momentum = Mass (kg)*velocity (m/s). 
Your initial velocity is zero, hence your initial momentum is zero. Therefore, if you know the mass of the marble, you can find the velocity by multiplying your force and the amount of time you blow. (I imagine you click and hold for a certain time to determine how long you blow). 
Keep in mind that momentum has direction, I.E. it is a vector. Therefore, if you want your marble to turn 90 degrees, you would need to first apply a force in the opposite direction, and then apply a force in the direction of your turn. 
EDIT: 3) If you do want to use friction (since the above method is clunky) what I would do is just have the velocity decrease by a constant rate every second. Maybe roll a marble on a flat surface in real life, see how long it takes to stop, and approximate a rate from there.
A: The wind is applying a pressure that corresponds to the velocity of the wind, this is fairly easy to calculate, see this wind load and wind speed, calculations.
Now should you want to take into account the drag coefficient as done here, than you should look up that coefficient, however for a sphere I would just use 0.5. 
Now as for the speed and such I would do the following. Assume two forces, one is the wind and the other is a weaker opposing force. You can go about this in two way the opposing force, let's call it friction, either only act when the ball is moving OR it linearly scales with velocity. Then calculate acceleration from force and velocity from acceleration. So, $a = Force / mass$ and $v = a \cdot time$. Your force depends on how hard someone blows but to be honest you can use any force you want as it's a game, thus you can set it to something that visually makes sense. Keep in mind to calculate the acceleration that I mentioned you need to sum all forces, so wind force + friction force, which should be in opposite directions. Basically friction is something like $F_{fr} = -v \cdot \mu$, where you just chose $\mu$ so that the values make sense in your game.
Keep in mind it's a game, these don't need to be all researched values.
