In this question use g=9.81 m s−2g = 9.81 \text{ m s}^{-2}g=9.81 m s−2.
A particle is projected from a point OOO with an initial speed uuu at an angle of 40∘40^\circ40∘ above the horizontal.
The particle lands at a point PPP which is 15 metres vertically below the level of OOO.
The particle takes 1.2 seconds to reach the maximum height of its trajectory.
Find the value of uuu.
Find the total time that the particle is in flight.
