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Homework Statement
There is one particle traveling at a constant velocity. Its velocity vector and initial position are known.
A second particle needs to collide with the first particle. We know the initial position of this particle, and the speed (magnitude of velocity).
Find the direction that the second particle needs to head in the hit the first particle.
We can assume the second particle is moving much faster than the first particle, so there will never be a case where the second particle cannot reach the first particle.
Example: Object A is moving in a straight line and we are trying to "shoot" another object at A so that they collide (like leading a moving enemy in a firefight).
Homework Equations
Let [tex]p_{1}[/tex] be a particle with a constant velocity
[tex]v_{1}[/tex] is the vector for the initial velocity of that particle.
Position: [tex]p_{1} = p_{1_{0}} + v_{1}*t[/tex]
We know everything there is to know about [tex]p_{1}[/tex] (it's initial position and its velocity vector)
Let [tex]p_{2}[/tex] be another particle with a constant velocity
[tex]v_{2}[/tex] is the vector for the initial velocity of that particle.
Position: [tex]p_{2} = p_{2_{0}} + v_{2}*t[/tex]
We know the initial position of this particle as well as the magnitude of its velocity. So given its speed and the other objects velocity: what would the direction need to be so that they collide.
The Attempt at a Solution
When the collision happens [tex]p_{1} = p_{2}[/tex]; so [tex]p_{1_{0}} + v_{1}*t = p_{2_{0}} + v_{2}*t[/tex]
We do not know [tex]t[/tex] or [tex]v_{2}[/tex] but we do know [tex]\sqrt{v_{2_{x}}^{2} + v_{2_{y}}^{2}}[/tex]
I tried splitting up the position equation into an equation for x and a separate equation for y.
After that I solved for [tex]v_{2_{x}}[/tex] and [tex]v_{2_{y}}[/tex] and then plugged it into the equation for the magnitude.
I simplified it but it was really complex and I couldn't solve for [tex]t[/tex].
I'm not sure what to try next.p.s. This is an informal question; it's possible that the problem is unsolvable. Also, I can draw a picture and scan it in if necessary.