Optional ReadonlyaccelerationAcceleration vector. Most applied forces will alter the acceleration, culminating in a new velocity being set and the acceleraton value zeroed
Optional ReadonlyangleOptional ReadonlyangularOptional ReadonlyangularOptional ReadonlymassMass. The unit is undefined, again best to think of this being on a 0..1 scale. Mass is particularly important for the attraction/repulsion force, but other forces can incorporate mass too.
Optional ReadonlypositionPosition. Probably best to use relative coordinates
Optional ReadonlyvelocityVelocity vector. Probably don't want to assign this yourself, but rather have it computed based on acceleration and applied forces
Basic properties of a thing that can be affected by forces