Abullet shot straight up returns to its starting point in 10 s. what is the initial speed of the bullet, assuming negligible air resistance?

Time to return = flight time = 10 s

Time to reach the maximum height = flight time / 2 = 10s / 2 = 5s

Speed at the maximum height = Vf = 0

Velocity formula: Vf = Vo - g*t => Vo = Vf + gt

     Vf = 0
     g = 9.8 m/s^2
     t = 5s

Vo = 0 + 9.8 m/s^2 * 5s = 49 m/s

49 m/s 
 

Gravity bc it’s gravity

Lx bxh