How Do You Calculate the Initial Speed of the Second Stone?

AI Thread Summary
To calculate the initial speed of the second stone, it's essential to first determine the time it takes for the first stone to hit the water after being dropped from a height of 47.0 m. The first stone, dropped from rest, will fall under the influence of gravity, allowing the use of kinematic equations to find its fall time. The second stone is thrown 1.48 seconds later, and both stones hit the water simultaneously, which means the time of flight for the second stone must account for this delay. Understanding the relationship between the time of the first stone and the initial speed of the second stone is crucial for solving the problem. The discussion emphasizes the need for clarity in applying kinematic equations to find the required values.
kmshowalter
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Homework Statement



A stone is dropped into a river from a bridge 47.0 m above the water. Another stone is thrown vertically down 1.48 s after the first is dropped. Both stones strike the water at the same time. What is the initial speed of the second stone?

Homework Equations


The Attempt at a Solution



What I'm not understanding is how to find the initial velocity of the first stone. I'm pretty sure you need that to figure out the initial speed of the second stone. At first I thought I needed to do 47/1.48s but when I did that I realized I didn't understand what that number would even represent. I know that I need an equation that will give me the time for both stones.
 
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kmshowalter said:

Homework Statement



A stone is dropped into a river from a bridge 47.0 m above the water. Another stone is thrown vertically down 1.48 s after the first is dropped. Both stones strike the water at the same time. What is the initial speed of the second stone?

Homework Equations





The Attempt at a Solution



What I'm not understanding is how to find the initial velocity of the first stone. I'm pretty sure you need that to figure out the initial speed of the second stone. At first I thought I needed to do 47/1.48s but when I did that I realized I didn't understand what that number would even represent. I know that I need an equation that will give me the time for both stones.

When something is "dropped" it is assumed to be released from rest. When something is "thrown" it is given some initial velocity.
 
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