You place a toy helicopter in a sealed lorry. Using accurate skills, you then cause the helicopter to hover inside the lorry but not changing its forward or sideways movements. If the lorry were to start moving. Would the helicopter move with it, or would it slowly move towards the back of the lorry befor ehidding the doors? To further confuse the issue. If you were inside a sealed lorry traveling at 70kph, and you got the helicopter to lift off perfectly vertical with no forwards or sideways movements, if the lorry sped up would it cause the helicopter to move backwards?