A projectile is launched from a point O O\,O on a horizontal level plane with an initial velocity of v m s−1v \text{ m s}^{-1}v m s−1 at an angle α \alpha\,α to the horizontal. The projectile needs to clear a horizontal distance of s s\,s metres before it hits the ground.
By modelling the projectile as a particle and neglecting air resistance, show that
sin2α≥sgv2 \sin 2\alpha \ge \frac{sg}{v^2} sin2α≥v2sg91 exam-style questions on OCR (MEI) A Level Maths 3.3 Projectiles (A-level only), covering 3.3.1 Model motion under gravity using vectors (A-level only), 3.3.2 Position, velocity, range and maximum height (A-level only), 3.3.3 Find the initial velocity of a projectile (A-level only), 3.3.4 Equation of the trajectory (A-level only), and 3.3.5 Solve simple projectile problems (A-level only). Each one has a worked solution and a mark scheme showing where the marks go.