Question

an athlete completes one round of a circular track of diameter 200 m in 40 s.what will be the distance covered and the displacement at the end of 2 minutes 20 s

Answer 1

Solution :
   Here, 
             Diameter (D) = 200 m
       So, Radius (R) = (D/2) = (200/2) m = 100 m
  We know,
       Circumference of circular track = 2πR
                                                         = 2×π×100
                                                         = 628.57 m
  2 minutes 20 s = 140 s 
    Now, 
 In 40 s, he covers distance of 628.57 m
 In 1 s , he covers distance of (628.57/40) m
 In 140 s , he covers distance of [(628.57/40)×140] m

Hence, an athlete covers distance of 2200 m in 2 min 20 s .