A person is standing at a distance 's' m from a bus. The bus begins to move with cosntant acceleration 'a' `m//s^(2)` away from the person. To catch the bus, the person runs at a constant speed 'v' m/s towards the bus. Minimum speed of the person so that he can catch the bus is:

Options

A. `sqrt(2as)`
B. `sqrt(as)`
C. `sqrt(3 as)`
D. `sqrt((as)/(3)`

Answer

A

Explanation

`v_(t) = s + (1)/(2) a t^(2)`
`:. T = (v +- sqrt(v^(2) - 2as))/(a)`
So, the passenger will catch the bus if t is real,
`:. V^(2) ge 2as`
`rArr u ge sqrt(2as)`