70. Water Stream Ballistics

Ballistic Motion is studied with a water stream that continually shows the parabolic trajectory of particles in a gravitational field. Measuring rulers hang down near the stream so that you can show, for example, that the stream falls a distance 1/2 gt� below the straight line it would have followed had there been no gravity. You can vary the angle of projection to show the 45° angle of greatest range, equal ranges at equal angles about 45°, etc. This demostration has audience appeal as the water pressure varies, and the instructor struggles to make the measurements while occasionally getting spritzed.