How Do Particles P and Q Collide in Vector Terms?

jdklek
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Hi guys, I'm reallyyyy stuck on this so I would really appreciate your help, cheers :)




2. Particle P passes through posiion A (12,3) with constant velocity i + 2j m/s. At the same time Particle Q passes through position B (3,-3) with c.v 2.5i + 3j m/s. Find the position vectors of P and Q after time t seconds. Show that they collide. If the point of collision is X, find the time taken for P to travel from A to X. Find the position vector of X.



3. It's just finding the position vector of X that I need help with...please?! :D
Thankyouu!
x
 
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What have you done so far?
 
Have you found the position vectors (as functions of t) for P and Q to begin with?
 
jdklek said:
Hi guys, I'm reallyyyy stuck on this so I would really appreciate your help, cheers :)




2. Particle P passes through posiion A (12,3) with constant velocity i + 2j m/s. At the same time Particle Q passes through position B (3,-3) with c.v 2.5i + 3j m/s. Find the position vectors of P and Q after time t seconds. Show that they collide. If the point of collision is X, find the time taken for P to travel from A to X. Find the position vector of X.
i and j are the orthogonal unit vectors in the plane:

\vec {v_P} = 1\hat i + 2\hat j \text{ m/sec}

and

\vec {v_Q} = 2.5\hat i + 3\hat j \text{ m/sec}

Write out the displacement of P from the origin as a function of time: d_P(x(t), y(t)) and do the same for Q.

What is the relationship between the displacements (ie the coordinates) of P and Q at the time of a collision?

AM
 
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The value of H equals ## 10^{3}## in natural units, According to : https://en.wikipedia.org/wiki/Natural_units, ## t \sim 10^{-21} sec = 10^{21} Hz ##, and since ## \text{GeV} \sim 10^{24} \text{Hz } ##, ## GeV \sim 10^{24} \times 10^{-21} = 10^3 ## in natural units. So is this conversion correct? Also in the above formula, can I convert H to that natural units , since it’s a constant, while keeping k in Hz ?
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