Aye. I don't see that there's any excuse for people not understanding this, we were taught about momentum prior to GCSE level Physics in school and I doubt my school was out of the ordinary in this.

I don't understand what the big deal is. Drive in a car at 2mph and throw a tennis ball up in the air and catch it again, the ball travels forward in relation to the ground at the same speed as you are moving. If at 10mph you throw it (gently) to someone in the back seat, the ball has gone backwards relative to you, but forward in relation to the ground. Simples. And, as you say, it means you simply cannot use the markings on the ground as an indicative guide, the only way you can really gauge the momentum of the ball relative to the player is to see where the player and ball are at in relation to each other at all times. (This, of course, is still open to 'cheating', as the bloke who threw the pass could deliberately speed up, hence why the referees look at the hands of the player passing the ball, as it's the only practical way they have of determining it from 'ground level')

I like the sound of this, though: m.dailytelegraph.com.au/sport/nr ... 6108565226

Seems like they plan to do live vector calculations to determine if the ball is propelled forward or backward.

Aye. I don't see that there's any excuse for people not understanding this, we were taught about momentum prior to GCSE level Physics in school and I doubt my school was out of the ordinary in this.

I don't understand what the big deal is. Drive in a car at 2mph and throw a tennis ball up in the air and catch it again, the ball travels forward in relation to the ground at the same speed as you are moving. If at 10mph you throw it (gently) to someone in the back seat, the ball has gone backwards relative to you, but forward in relation to the ground. Simples. And, as you say, it means you simply cannot use the markings on the ground as an indicative guide, the only way you can really gauge the momentum of the ball relative to the player is to see where the player and ball are at in relation to each other at all times. (This, of course, is still open to 'cheating', as the bloke who threw the pass could deliberately speed up, hence why the referees look at the hands of the player passing the ball, as it's the only practical way they have of determining it from 'ground level')

I like the sound of this, though: m.dailytelegraph.com.au/sport/nr ... 6108565226

Seems like they plan to do live vector calculations to determine if the ball is propelled forward or backward.