I have a conservation of momentum equation Q

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Discussion Overview

The discussion centers around a problem involving conservation of momentum and energy in a collision scenario. Participants explore the dynamics of a skeet being struck by a pellet, focusing on the subsequent height and horizontal distance traveled after the collision. The scope includes theoretical reasoning, mathematical calculations, and projectile motion analysis.

Discussion Character

  • Exploratory
  • Technical explanation
  • Mathematical reasoning

Main Points Raised

  • One participant presents the initial scenario involving a skeet and a pellet, suggesting the use of conservation of energy to determine the height and projectile motion to find horizontal distance.
  • Another participant outlines a step-by-step approach, including energy conservation for the skeet and conservation of momentum for the inelastic collision.
  • A participant questions the necessity of using a specific equation related to the horizontal velocity component.
  • One participant calculates an impact height of 11.43 m and seeks confirmation on its correctness based on the derived equation.
  • Another participant confirms the calculation is correct if the term "impact height" refers to the height of the skeet at the moment of collision.
  • A participant concludes that they can use conservation of momentum to find new velocity components and treat the problem as a standard 2D kinematics issue.

Areas of Agreement / Disagreement

Participants generally agree on the approach to solving the problem using conservation principles, but there are varying levels of confidence in specific calculations and interpretations of terms like "impact height." The discussion remains unresolved regarding the accuracy of the calculations and the implications of the results.

Contextual Notes

Some assumptions regarding the definitions of terms and the conditions of the collision may not be fully articulated, and there are unresolved mathematical steps in the calculations presented.

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I have a conservation of momentum equation Q!

A 0.25kg skeet (clay target) is fired at an angle of 30 degrees to the horizon with a speed of 30 m/s. When it reaches its maximum height, it is hit from below by a 15g pellet traveling vertically upward at a speed 200m/s, the pellet is imbedded in the skeet.

So they want to know how much higher the skeet would go, and how much EXTRA horizontal distance the skeet would travel because of that collision...

I believe you can get the height from using conservation of energy. Then you can use what you know about projectiile motion to find all the different time intervals involved. From there, Distance in the x direction is simply Vx*t

I am just not sure if I am getting the correct numbers? What would you guys do?
 
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Step 1.
Energy conservation up to maximal height h for the skeet:
[tex]\frac{1}{2}V_{0}^{2}=\frac{1}{2}V_{0,x}^{2}+gh[/tex]
([tex]V_{0}[/tex] is initial velocity, with components [tex]V_{0,x},V_{0,y})[/tex]
Step 2. Conservation of momentum in inelastic collision.
This will yield a non-zero upwards velocity component.
Step 3. Book-keeping:
Record horizontal distance already traveled, [tex]X_{1}[/tex], and vertical and horizontal velocities after collision.
Step 4.
Solve for landing position as a function of time, using parameters obtained in Step 3.
 
But since Vo x is constant why would you use that equation to solve it?
 
Because I forgot to eliminate it on both sides of the equation..
 
I get an impact height of 11.43 m. Is this correct? (Using your equation.)
 
If [tex]11.43=\frac{(30\sin30)^{2}}{2g}[/tex], then it is correct, as long as you with "impact height" means the height of the sleet when the proctile hits it.
 
Cool then I just use conservation of momentum to find the new Vx and Vy and treat it like an ordinary 2D kinematics problem.
 
Yes; that would be it.
 

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