Interesting article on BBC at the moment...
 
Apparently the key to assessing the speed of a vehicle is the change in size or "looming"
 
They tested kids and it suggests that whilst adults can assess a 6 mph diffrence in speed, it is 20 mph in some children and elderly
 
That is they cannot tell whether a car is travelling towards them at 20 mph or 40 mph, and hence may cross a road when it is in fact unsuitable to do so
 
Interesting concept
	
		
			
		
		
	
			
			Apparently the key to assessing the speed of a vehicle is the change in size or "looming"
They tested kids and it suggests that whilst adults can assess a 6 mph diffrence in speed, it is 20 mph in some children and elderly
That is they cannot tell whether a car is travelling towards them at 20 mph or 40 mph, and hence may cross a road when it is in fact unsuitable to do so
Interesting concept