A staircase contains three steps each 10 cm high and 20
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A staircase contains three steps each 10 cm high and 20 cm wide figure . What should be the minimum horizontal velocity of a ball rilling off the uppermost plane so as to hit derectly the lowest plane ?
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Right Answer is:
SOLUTION
At minimum velocity, it will move just touching the point E and reaches the ground.
A is origin of preference co-ordinate
.
If u is the minimum speed,
x = 40, y = -20, θ=00
∴ y = tan~θ−g x2 sec2 θ2u2
Where g = 10m/s2=1000cm/s2
⇒−20=−8000002u2
⇒u=200cm/s=2m/s
∴ The minimum horizontall velocity is 2 m/s.
