A ball is thrown vertically upward, which is the positive direction. a little later it returns to its point of release. the ball is in the air for a total time of 8.00 s. what is its initial velocity? neglect air resistance.
Final Velocity = Vf = 0 m/s --------------> (Vf = 0 because ball's speed at its max height is 0)
Initial Velocity = Vi = ?
Total time (upward & downward) = 8.0 seconds
* Time upward = 4 seconds & ................( As time for ball upward & downward is equal )
* Time downward = 4 seconds..
Gravitational Acceleration = g = -9.8 m/s²
Use Equation;
Vf = Vi - gt
0 = Vi - 9.8 * 4
0 = Vi - 39.2
39.2 = Vi
=> Vi = Initial Velocity = 39.2 m/s
