Physics Help!!!

Question

For a baseball to travel 90 meters, with what velocity must it be hit if the angle of impact is 40°? Flight time is 3.9 seconds.

Answer 1

We're given Δx = 90 m, angle = 40°, and t = 3.9 s. The horizontal velocity v_x, which is constant in these problems, is a component of total initial velocity v_o: v_x = v_o cos 40° = Δx / t = (90 m) / (3.9 s) = 23.₀₈ m/s. Then v_o = (23.₀₈ m/s) / cos 40° = 30. m/s [I assume 2 sig figs].