“If a plane is traveling at takeoff speed on a conveyor belt, and the belt is matching that speed in the opposite direction, can the plane take off?”
So if they are traveling the same speed,the plan is staying in one place. Lift can only be created with air moving.No air moving=No lift.If you run on a treadmill you feel no air moving because you’re stationary.If you run on the road you feel air because you’re moving forward.