A staircase contains three steps each 10 cm high and 20 cm wide as shown in the figure. What should be the minimum horizontal velocity of a ball rolling off the uppermost plane so as to hit directly the edge of the lowest plane ? [g = 10 m//s^(2)]

A staircase contains three steps each 10 cm high and 20 cm wide as sho

1.	A staircase contains three steps each 10 cm high and 20 cm wide as shown in the figure. What should be the minimum horizontal velocity of a ball rolling off the uppermost plane so as to hit directly the edge of the lowest plane ? [g = 10 m//s^(2)]
Answer» Solution :h = 30 cm `S = 60 cm = vsqrt((2h)/(50))` `= vsqrt((2 xx 30)/(1000)) = vsqrt((3)/(50))` `therefore v = (60)/(100) SQRT((50)/(3)) = (3)/(5) xx 5sqrt((2)/(3)) = sqrt(3) xx sqrt(2)` `= 2.45m//s`