Hello there everyone,

I'm here because I'm using Portal 2 in my research for my masters degree in science education. Basically I'm doing a study to figure out if Portal 2 (and by extension "virtual reality") helps students learn Newton's Laws and makes them more excited to learn about physics.

I've designed an after-school program where the kids will come in and learn about Newtons Laws, play Portal 2, learn how to use the Puzzle Maker, and design their own puzzles. They will have three main assignments - building a puzzle that demonstrates each of Newton's Three Laws at some point in the puzzle.

I'd like to reach out to the Portal 2 mapping community for help brainstorming ways that this can be accomplished to get a better idea on what potential ways the students will be able to complete the assignments.

In particular, I'm having trouble thinking of how they could demonstrate the second law - F=ma (the acceleration experienced by an object in response to a force is proportional to it's mass). There doesn't seem to be any way I can vary mass, or add friction to surfaces, etc...in order to provide opposing forces or produce accelerations that are different (every cube is going to respond the same way to a given force, for example)

Any ideas you may have on how any of Newton's Laws can be demonstrated with Portal 2 and with the Puzzle Maker, I would be incredibly grateful if you could post them here! Here are the laws for reference:

1. Law of Inertia - Objects tend to stay in motion (or at rest) unless an external force is applied.
2. F=ma - The acceleration experienced by an object in response to a force is proportional to the objects mass.
3. For every action there is an equal and opposite reaction.

Thanks in advance everyone!

Valve actually made an educational version of Portal 2/the Puzzlemaker with special cubes you can change the properties of, faith plates that apply a certain force and a few other things. If you can get a hold of it, that might be useful. http://www.teachwithportals.com/

That site was what spawned my research! Unfortunately, they seem to have discontinued their support for that program. I have inquired about how to get a hold of the educational version, but have not received a response yet. I was really looking forward to being able to use it, though. Now I'm just trying to figure out how to continue the research without it.

1) The law of inertia:
That's clearly a bit of a problem since there's air friction in portal on physics objects.
That means:
If you throw a cube from height 1; and let it go through 2 portals on the floor; eventually it will lose height.
Players themselves don't lose this momentum though.

The second paragraph might be easier to implement: objects tend to say in rest.
I can imagine for example cubes balancing on edges or something; where the center of mass is still stable; but as soon as it gets a bit of force applied it tumbles over.

2 F=ma; I think faithplates demonstrate this very well; the educational version of portal 2 has a very awesome system in place where you can increase the mass of cubes etc. As for not getting contact with valve; you can always try to e-mail the boss with your project: gaben [at] valvesoftware.com

The weight-changing cubes also allow a good insight on the second and third law; Having two same-weight-cubes bang their heads together in mid air will let them go the same distance from the middle; where as if you have a heavy one and light one smash their heads together you get a much less even displacement of the cubes.

So yeah; I would totally recommend trying more channels to get the educational version of the game, since that version has way more tools to properly show how physics work

Speed gel is useful for demonstrating all three laws, as it makes friction almost negligable. For example, if you knock over a turret on an orange surface its recoil will send it flying. I don't know how strong a force it has, but it might be able to kill a second turret or knock a (speed-painted) box off a ledge.

For the second law, if you had different masses of cubes (which would be fairly trivial to add with a straight editoritems change, if you don't want to deal with the BEE2) you could launch them off the same faith plate (constant force) and watch them go different distances. Perhaps you have two tbeams at different heights which press cubes onto buttons, and the player needs to launch one cube into each to open the door?

The first law, as Lp said, is probably the hardest. Maybe you could propel a cube down a speed-painted track and observe that it doesn't slow down very much? The double-floor-portal-fling is a good idea, but there's an outside force doing work on the player the whole time.

The third law is hard to demonstrate in a game because you don't have the sensation of touch. In real life you could just punch a wall and say "the wall exerted a force upon me when I exerted a force upon it". So you may be hard pressed to come up with something that accurately depicts it.

However, two spheres hitting each other in mid-air (launched via faithplate) could satisfy it to some degree - each cube exerts a force on the other, and as such the reaction force causes them to change course and move in a different direction.

The second law could be having a ball stay still (somehow) until something like a panel opening would force the ball to move and watching a cube in comparison.
The third law could be demonstrated by turrets covered in orange gel being knocked over and shooting on the wall and slipping to the opposite direction.