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Problem
The circular disc of radius 饾煋饾拵 is divided into 7 equal parts and colored in the sequence "饾懡饾懓饾懇饾懏饾拃饾懚饾懝". What is the minimum velocity at which it will seem white to a human? (Persistence of human vision is 饾煄.饾煆饾挃
Solution
We know, velocity v = distance 饾挃/time t.
=> v = 2蟺r/t
=> v = 2脳3.1416脳5/0.1
=> v = 314.16 饾拵饾挃-1
#problems_001