The velocity of two objects as they meet

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The discussion centers on a physics problem involving a 30-gram dart shot upwards at 9.1 m/s and a 25-gram cork ball dropped from a height of 2.6 meters. Participants clarify the importance of including units in calculations and emphasize the need to determine the velocities of both objects just before impact to solve for the speed after the inelastic collision. One suggestion is to write equations for the positions of both objects as functions of time and set them equal to find the collision point. The conversation highlights the challenges of the problem, particularly in calculating the time and velocities accurately. Understanding the dynamics of the collision is crucial for determining the final speed of the cork ball after being hit by the dart.
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A 30 dart is shot straight up at 9.1 . At the same instant, a 25 ball of cork is dropped from 2.6 above the dart.

What is the speed of the cork ball immediately after it is hit by the dart? Assume the collision is exactly head-on and the dart sticks in the cork.

So I assumed it was an inelastic problem; but when I looked at it; i realized that the initial velocity of both objects could only be assumed right before they hit. Both of the objects have an acceleration of 9.81 downwards; I need to find the velocity right before impact to be able to determine the speed after the impact right?

Thanks in advance!
 
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hazard808 said:
A 30 dart is shot straight up at 9.1 . At the same instant, a 25 ball of cork is dropped from 2.6 above the dart.

What is the speed of the cork ball immediately after it is hit by the dart? Assume the collision is exactly head-on and the dart sticks in the cork.

So I assumed it was an inelastic problem; but when I looked at it; i realized that the initial velocity of both objects could only be assumed right before they hit. Both of the objects have an acceleration of 9.81 downwards; I need to find the velocity right before impact to be able to determine the speed after the impact right?

Thanks in advance!

What in the world is a "25 ball"? Please include units in all of your quantities and calculations.
 
sorry its a 30 gram dart and a 25 gram ball; I can't believe I forgot units haha
 
What I initially did was try and equal the distances, but the math just led me in circles; I mean when as they meet I should be able to find time right? Unfourtunately this unit did not help in any respects I did not find what I was looking for. Silly me eh? thanks for any help :)
 
Perhaps write equations for both of their positions as a function of time and then set them equal to one another to find when they'll collide. From there you can find their velocities.
 
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