Free fall acceleration (time elapsed, initial & final speed)

AI Thread Summary
A rock climber throws two stones from a 50-meter cliff, observing a single splash when they hit the water. The first stone, thrown with an initial speed of 2.0 m/s, takes approximately 2.98 seconds to reach the water. The second stone, released 1 second later, also hits the water at the same time, meaning it takes 1.98 seconds to fall. To achieve this, the second stone must have an initial speed that compensates for the shorter fall time. The problem illustrates the effects of gravity and initial velocity on free fall dynamics.
sona1177
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Homework Statement


A rock climber stands on top of a 50-m-high cliff overhanging a pool of water. He throws two stones vertically downward 1.0 s apart and observes they cause a single splash. The initial speed of the first stone was 2.0 m/s.

a) How long after the release of the first stone does the second stone hit the water?
b) What was the initial speed of the second stone?
c) What is the speed of each stone as they hit the water?

Homework Equations


V = Vo + at
Y - Yo = Vot + .5at2
v2 = vo2 + 2a(Y - Yo)
Y - Yo = .5(Vo + V)t

The Attempt at a Solution


The problem I am having is that I don't know how to take account the time difference. For instance, you are not just solving for t but have to take into account that one was dropped 1 second after the other. For the first stone, I calculated a time of 2.98 seconds using formula Y - Yo = Vot + .5at2
Y=-50 m
Yo=0m
Vo=-2 m/s
t=?
ay=-9.8 m/s^2

Label Axis: I am assuming the up direction is positive and down direction is negative.

I can't proceed to parts B and C until I know A. Please Help! Thank you very kindly.
 
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A single splash is seen, hence they hit the water at the same time. Thus, given the initial velocity of the first stone, and the acceleration due to gravity, how long does it take for it to hit the water?

For b, if it is to cover the same distance in the time it takes a - 1second, what must that stone's initial velocity be?
 
sona1177 said:
For the first stone, I calculated a time of 2.98 seconds
So, you solved it :)

a) Because both stones splash at the same moment - the second stone hit the water 2.98s after the release of the first stone.
 
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