We consider the motion of a particle launched obliquely under gravity force and air resistance proportional to velocity. We obtain, via differential calculus, general informations about the trajectory of the particle as increasing and decrease intervals, maximum point, concavity, asymptotic behavior, horizontal reach etc., allowing us tracing the profile of this trajectory without the use of numerical tables and without the need to make approximations. We present a demonstration that, although there is no explicit exact expression for the horizontal reach of the particle, it is always smaller as larger the value of air resistance parameter, which matches the physical situation under consideration.
Keywords:
oblique launch; air resistance; trajectory; horizontal reach
