posted by sedef .
A science student is riding on a flatcar of a train traveling along a straight, horizontal track at a constant speed of 12.8 m/s. The student throws a ball into the air along a path that he judges to make an initial angle of 67.0° with the horizontal and to be in line with the track. The student's professor, who is standing on the ground nearby, observes the ball to rise vertically. How high does she see the ball rise?
h=v₀²/2g= (v•sinα)²/2g= (12.8•sin67º)²/2•9.8=7.08 m.