Receiving the ball

Worked example 1: aiming the platform. When a ball rebounds from a flat surface without spin, it leaves at about the same angle to the surface as it arrived (angle in = angle out). So the platform must face halfway between the direction the ball comes from and the direction of the target.

1. A serve comes straight at you along the length of the court. The setter is 2 m in front of you and 2 m to your right, so the target is ${\tan }^{-1}\frac{2}{2}={45}^{\circ }\backslash tan^\{-1\}\backslash frac\{2\}\{2\}\; =\; 45^\{\backslash circ\}$ to your right.
2. Face the platform halfway: $\frac{0^{\circ }+{45}^{\circ }}{2}={22.5}^{\circ }\backslash frac\{0^\{\backslash circ\}\; +\; 45^\{\backslash circ\}\}\{2\}\; =\; 22.5^\{\backslash circ\}$ to the right.
3. If the setter were 1 m to the right and 3 m in front, the target would be ${\tan }^{-1}\frac{1}{3}={18.4}^{\circ }\backslash tan^\{-1\}\backslash frac\{1\}\{3\}\; =\; 18.4^\{\backslash circ\}$ to the right, and the platform should turn about 9° to the right.

Turning the shoulders and the platform, not swinging the arms sideways, is what sends the ball to the target. Real passes also lose energy and spin, so players fine-tune the angle by practice.

Worked example 2: judging reception. A team receives 12 serves in a set: five passes rated 3, four rated 2, two rated 1 and one rated 0 (illustrative).

1. Total score: $5\times 3+4\times 2+2\times 1+1\times 0=15+8+2+0=255\; \backslash times\; 3\; +\; 4\; \backslash times\; 2\; +\; 2\; \backslash times\; 1\; +\; 1\; \backslash times\; 0\; =\; 15\; +\; 8\; +\; 2\; +\; 0\; =\; 25$.
2. Average: $\frac{25}{12}=2.08\backslash frac\{25\}\{12\}\; =\; 2.08$.
3. Perfect-pass rate: $\frac{5}{12}=42\mathrm{\%}\backslash frac\{5\}\{12\}\; =\; 42\backslash \%$.

An average above 2 means the setter can usually set an attack. Coaches use the same scores to find which receiver, and which part of the court, needs more practice.