What are the kinematic equations for projectile motion?

[afcwestwarrior]

Homework Statement

A pitcher throws a ball at an angle 37 degrees with the horizontal and observes that the ball stays in the air for 2.5s before hitting the ground. Neglecting air friction and the height of the pitcher, find
(a) the initial speed of the ball
(b) maximum height reached by the ball
(c) how fast would the pitcher have to run (at constant speed) to catch his own ball?

Homework Equations

v=Vinitial + at
x-xinitial=vinitial (t)+ 1/2 a t^2

basically the kinematic equations

The Attempt at a Solution

Vi=?
Vfinal=0
Ax=0
change in x=?
g=-9.8m/s^2

ok what do i do

 

[LowlyPion]

Homework Statement

A pitcher throws a ball at an angle 37 degrees with the horizontal and observes that the ball stays in the air for 2.5s before hitting the ground. Neglecting air friction and the height of the pitcher, find
(a) the initial speed of the ball
(b) maximum height reached by the ball
(c) how fast would the pitcher have to run (at constant speed) to catch his own ball?

Homework Equations

v=Vinitial + at
x-xinitial=vinitial (t)+ 1/2 a t^2

basically the kinematic equations

The Attempt at a Solution

Vi=?
Vfinal=0
Ax=0
change in x=?
g=-9.8m/s^2

ok what do i do

Start with the Vy. You know how long it takes to go up and then goes down. What does that translate into as far as initial velocity up?

 

[afcwestwarrior]

it's positive

 

[LowlyPion]

it's positive

and ... ?

 

[afcwestwarrior]

i don't know

 

[LowlyPion]

i don't know

Here are some kinematic formulas that might help:
https://www.physicsforums.com/showpost.php?p=905663&postcount=2

Though one of the formulas you listed would help you find the Vy given that you know the time up and back down.