projectile motion physics questions?

Question

Several questions in my homework that i just could not figure out. please help (:

formulas::

vertical
distance= 1/2 * g * t^2
velocity= g * t

horizontal
distance= v * t
velocity= d/t

2. In baseball, a fastball takes about 1/2 seonds to reach the plate. Assuming that such a pitch is thrown horizontally, compare the distance the ball falls in the first 1/4 seconds with the distance it falls in the second 1/4 seconds.

5. a quarterback threw a football at 24 m/s at a 45 angle. If it took the ball 3 seconds to reach the top of its path, how long was it in the air?

Answer 1

I think I know how you feel :-(

Free fall (as you have said)
h= 0.5 gt^2 so

first 0.25 sec
h=0.5 g (0.25)^2=g/32

second 0.25 sec

h=0.5 g (0.5)^2 - 0.5 g (0.25)^2
h= g/8 - g/32= g3/32

That means it traveled 3 times more the second 1/4 sec than the first 1/4 sec

5. The time it takes for the ball to go up must be the same time it will take it to fall to the same height it was released. (No air influence, no resistance...)

t=t(up) + t(down) and since t(up) =t(down)
t=2 (3)=6 sec