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A ball rolls off the top of a stairway with horizontal velocity u. The steps are 0.1 m high and 0.1 m wide. The minimum velocity u with which that ball just hits the step 5 of the stairway will be x ms-1 where x= [use g=10 m/s2].
2
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To land on step 5 with least u, the ball must just clear the edge of step 4:
x=0.4 m, y=0.4 m
x=ut, y= 12gt2 0.4= 12 10 ( 0.4u )2
u2= 5 0.160.4=2
u= 2 m/s x=2
Answer: 2
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