A supply crate is fired from a pneumatic launcher standing on a flat horizontal plain. The crate leaves the launcher at ground level with initial speed U U\,U m s−1^{-1}−1 at an angle θ \theta\,θ above the horizontal.
To reach a medical camp a horizontal distance X X\,X metres away, the crate must travel at least that distance before its first impact with the ground.
The crate is modelled as a particle moving freely under gravity, with gravitational acceleration g g\,g constant.
By finding the time of flight and hence the horizontal distance travelled, show that sin2θ≥XgU2\sin 2\theta \ge \dfrac{Xg}{U^2}sin2θ≥U2Xg.
204 exam-style questions on CCEA A Level Maths 4.1 Kinematics (A-level only), covering 4.1.1 Kinematics (A-level only), 4.1.2 Kinematics (A-level only), and 4.1.3 Kinematics (A-level only). Each one has a worked solution and a mark scheme showing where the marks go.