A radar observer on the ground is \"watching\" an approaching projectile. At a certain instant she has the following information: the projectile is at maximum altitude and is moving horizontally with speed v; the straight-line distance to the projectile is L; the line of sight to the projectile is at an angle e above the horizontal. (a) Find the distance D between the observer and the point of impact on the projectile. D is to be ex- pressed in terms of the observed quantities v, L, 𝜃 and the known value of g. Assume a fiat Earth; assume also that the observer lies in the plane of the projectile's trajectory. (b) How can you tell whether the projectile will pass over the observer's head or strike the ground before reaching her?
Hrishant Goswami , 9 Years ago
Grade 10
