The velocity of two objects as they meet

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Discussion Overview

The discussion revolves around a physics problem involving the collision of a dart and a cork ball. Participants explore the dynamics of the situation, including the initial velocities, accelerations, and the nature of the collision, which is assumed to be inelastic. The focus is on determining the speed of the cork ball immediately after it is struck by the dart.

Discussion Character

  • Exploratory
  • Technical explanation
  • Homework-related
  • Mathematical reasoning

Main Points Raised

  • One participant proposes that the problem is an inelastic collision and emphasizes the need to find the velocities of both objects just before impact to determine the speed after the collision.
  • Another participant questions the clarity of the problem by asking for units in the quantities and calculations, indicating a need for precision in the problem statement.
  • A participant clarifies that the dart is 30 grams and the cork ball is 25 grams, acknowledging a previous omission of units.
  • One participant suggests writing equations for the positions of both objects as functions of time and setting them equal to find the collision time, which could then lead to determining their velocities.
  • Another participant expresses frustration with their initial approach of equalizing distances, indicating that they did not find the expected results and are seeking further assistance.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the best approach to solve the problem, as there are multiple suggestions and some confusion regarding the initial conditions and calculations. The discussion remains unresolved with various methods proposed.

Contextual Notes

There is uncertainty regarding the initial velocities of both objects right before impact, and the problem's setup may depend on specific assumptions about their motion. The discussion highlights the need for clarity in units and definitions.

Who May Find This Useful

This discussion may be useful for students or individuals interested in physics problems involving collisions, kinematics, and the application of mathematical reasoning to real-world scenarios.

hazard808
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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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