Rugby Player Collision Question-

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Two rugby players, one accelerating from rest at 0.5 m/s² and the other moving at a constant speed of 3.1 m/s, are 37 meters apart. To determine how long it takes for them to collide, the equations of linear kinematics are applied, focusing on displacement and time. The problem involves isolating displacement and setting up two equations based on their respective distances traveled. The solution process includes using the quadratic formula to find the time until collision. The discussion highlights the importance of understanding kinematic equations in solving such motion problems.
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Rugby Player Collision Question--

Homework Statement



Two rugy players are running towards each other. They are 37 m apart. If one is accelerating from rest at 0.5m/s² and the other was already moving at 3.1 m/s and maintains her speed,

a) how long before they crunch together?
b) how fast was the accelerating player going?
c) how far has each player run?

Homework Equations



In this situation: The five equations of linear kinematics

v2 = v1 + a∆t
∆d = ½(v2 + v1)∆t
∆d = v1∆t + ½a∆t²
∆d = v2∆t - ½a∆t²
v2² = v1² + 2a∆d

The Attempt at a Solution



37-d= a(d/v)²/2
37-d= a(d²/v²)/2
74-2d= a(d²/v²)...

And I trailed off from there as I was confused. Now I know you may have to isolate the displacement in this case, however I have not yet encountered a question like this before and it was not clearly explained to me beforehand. Hopefully I'll know what to do through these forums.
 
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One travels d and the other travels 37-d.

They meet at the same time, so find two equations in the two unknowns d and t.
 
I thought it revolved around that, thank you. I used the quadratic formula and found two roots, which was my time for both rugby players, and it went smoothly from there.
 
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