Freefall, is the answer really 20 ?

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A lead ball is dropped from a height of 5.0 meters into a lake and takes 3 seconds to sink to the bottom after hitting the water. The calculations indicate a final velocity of 9.89 m/s, leading to a depth estimate of 29 meters based on the sinking time. However, there is confusion regarding the timing of the 3 seconds and whether it refers to the time after the ball hits the water. The expected answer is 20 meters, prompting a discussion about the accuracy of the original problem statement and the equations used. Clarification on the timing and methodology is needed to resolve the discrepancy.
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Homework Statement



A lead ball is dropped into a lake from a diving board 5.0 m above the water. After entering into the water it sinks into the bottom with a constant velocity which it hit the water for 3 seconds. and hits the bottom of the lake. How deep is the late ?

Homework Equations


Vf ² - Vi ² = 2as


The Attempt at a Solution



Well I just used this equation and I get a velocity of 9.89 which I find odd. I think it should take less then 1 second to hit the water.

I get an answer of 29 meters by finding out the velocity and multipling by 3 seconds.
Altho in the answers it says 20.
 
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You should be right. It didn't say 2 seconds?
 
did you post the question exactly? Is the 3 seconds after it hits the water? I'm confused by this part:

"which it hit the water for 3 seconds. and hits the bottom of the lake"
 
show more steps, i don't like the equation you used
 
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