How Do You Calculate Hang Time and Velocity in Cat Jump Kinematics?

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Homework Statement



In a 1985 study, cats were trained to jump up and touch a cotton ball in an effort to study their thigh muscles. One cat was able to jump 2.93 meters off the ground.

What is its hang time? In other words, what total time was the cat in the air?
s
What was its initial velocity?
m/s
What was its final velocity?
m/s

Vi and Vf do not equal 0
A = -9.8
D = 2.93 or 5.86
How does this make any sense? Don't I only have two variables (acceleration and displacement) and I need at least three to solve all of the kinematics?

Homework Equations



U1L6a1.gif


The Attempt at a Solution



I've used plenty of different equations and can't seem to find anything out.
 
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Think of its jump as two events: the cat jumps up, the cat falls down. What is its velocity at before and after each event?
 
Hint: you're not going to be able to answer your questions in order...
 
You know the maximum height the cat has reached - 2.93 m. If it had still some speed at that height it would have risen higher. So you have vf=0 when the displacement is 2.93 m. You can also find the time. Falling back takes the same time.

ehild