The specific measurement and shape
of the rugby league ball (determined by the International Rugby Board) give it
certain biomechanical characteristics to be exploited by the players.
As seen in the figure on the right, the measurements of a
standard rugby league ball are as follows:

Length: 28-30 centimetres
Width: 18.5-19.7 centimetres
End to end circumference: 74-77 centimetres
Width circumference: 58-62 centimetres
Weight: 410-460 grams
The Answer: The shape of a rugby league ball is described as
a rounder, egg like shape which can be referred to as the prolate spheroid (Lemoine & Naami 2013). A prolate
spheroid is spheroid that allows a rotation around the major axis, which
enforces a backward motion after the ball has been kicked allowing for greater
distance to be traveled and a predictable flight path. The length, width and
circumference of the ball make it less aerodynamic than an Australian Rules
football; however, its wide berth allows it to be more stable so that it can be
kicked a greater distance with more accuracy, which is important for the place
kick. The weight of the rugby ball is typically heavier than Australian Rules
footballs to reduce the effect of air resistance and high winds but, is still
light enough to be easily carried during play.
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