Some plants disperse their seeds when the fruit splits and contracts, propelling the seeds through the air. The trajectory of these seeds can be determined with a high-speed camera. In an experiment on one type of plant, seeds are projected at 20 cm above ground level with initial speeds between 2.3 m/s and 4.6 m/s. The launch angle is measured from the horizontal, with +90o corresponding to an initial velocity straight up and -90o straight down. The experiment is designed so that the seeds move no more than 0.20 mm between photographic frames.
What minimum frame rate for the high-speed camera is needed to achieve this?