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Simple wheel rotation question.

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I have a wheel on screen with numbers. Something like wheel of fortune. It''s divided into 32 areas (32 numbers) with same width of 11.25 degrees It starts to spin at constant speed 8 degrees each 20 ms (that''s the timer time). So it''s 400 degrees per second. I need to slow it down in couple (let''s say X) of seconds and stop on specific number. Let''s say i''m at number 18 right now and i need to slow it down and stop on number 3. So the slowdown path will be 551,25 degrees ((32-18)+3+32). 32 is an extra 1 loop rotation for smoother stop So now i need to find a number to decelerate the wheel each 20ms. From 8 degrees per 20 ms to 0 degrees... That has to do something with mechanics or angular rotation. But it was long time ago so i can''t remember anything. The problem is that I can change value only EACH 20 ms. Else I have the formula: v^2 = u^2 + 2*a*s u = initial velocity, v = velocity, a = acceleration, t = time, s = displacement (distance) So it will be 0^2 = 400^2 + 2*a*551,25 But when it comes to slowing down only 50 times a second this thing doesn''t work because of non-uniform deceleration. Here comes something like s = u*t + 0.5a * t*t But I can''t understand it. If somebody can take a look here: and explain it to me... Thanks in advance.

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