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## Homework Statement

A pitcher throws a ball vertically upward and catches it at the same lever 4.2 seconds later.

A) What velocity did the pitcher throw the ball?

B) What distance did the ball travel?

## Homework Equations

Vfy^2=Viy^2+2ay[tex]\Delta[/tex]y

[tex]\Delta[/tex]y=Viy+0.5ay([tex]\Delta[/tex]t)^2

## The Attempt at a Solution

we know

[tex]\Delta[/tex]t=4.2s

ay=+9.8m/s/s,[Up] -9.8m/s/s[Down]

Viy=?

Vfy=?

[tex]\Delta[/tex]y=?

Several attempts have failed lol. One was to take the balls maximum height as initial velocity=0 and try to figure out distance (y) and final velocity. epic fail.

I think my main problem is trying to understand how to re arrange these equations, depending on the quantity i am missing. The book suggests the use also of the quadratic equation, and epends all of 4 sentances explaining it. could it be used here?

One other question, in an attempt to better understand acceleration due to gravity.

Since he is throwing the ball up, at whatever velocity he throws it, the distance up will be the same as the distance down, providing he catches it on the same level (obviously) and since the the force slowing it down on the way up, gravity, at a rate of 9.8m/s/s is also the force and rate speeding it up on the way down the final velocity should be the same as initial velocity, right? forgive me if this is an extremely stupid obvious question haha, all this math is makeing my head spin