A bit of simple GCSE level physics, but explained in a rather roundabout way:
If a ball travels approximately horizontally towards a static object (lets say a horizontal bar) and hits the underside of said object, this will cause the ball to have backspin as it falls sharply downwards. Then, if as the ball comes down it comes into contact with a flat horizontal surface soon afterwards (the ground, say) the backspin will make it bounce backwards a bit in the direction of the horizontal plane from which it came. So, if it hits our static object (the bar) again upon bouncing up, and if we imagine there was a straight line (let’s say it’s white) on the floor immediately below our static object (the bar), it must have hit the ground beyond that line. If it hadn’t landed beyond the line, it would have missed the bar on the way back up.
Basically, what I’m saying is, the ref and his assistant could have figured out the ball had crossed the line simply from the fact that it hit the bar again as it bounced up. “Get over it” I hear you say. Maybe one day…
Here’s what I played tonight: Continue reading