A few questions I have for a game I am working on.

So, Im working on a simple physics game and I have a few questions on how I would get some things done.

  1. How can I modify the speed at which an object moves IN GAME?

  2. Do I need to set up an animation to make an object move at a set speed and set direction, for a set amount of time, or is there some logic I can set up to make a block move 15 units on the x axis at a force of 5. I ask because the way I have it set up now, the block moves more as I hold the space bar down.

  3. Is there an easy way to make uniform hills?

  4. Would it be possible to allow the player to modify the environment? IE, change the height of a hill, or the slope of an incline?

If these are SUPER NOOB, I apologize, and would appreciate any feedback. Thank you.