Solving the Convergence of Points A and B

AI Thread Summary
The discussion revolves around a problem involving two points, A and B, where A moves with a constant velocity v directed towards B, which moves at a uniform velocity u (with u < v). The initial conditions state that A and B are separated by a distance l, and their velocities are perpendicular at the start. The challenge lies in determining when A begins to turn towards B and how the changing direction of A affects convergence. Key considerations include the need for both points to cover the same distance in the same time, and the use of integrals to solve the problem. The conversation emphasizes the complexity of the motion and the importance of understanding the relationship between the velocities and the distance.
vaishakh
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Can anyone here give some hint to solve this question. I cannot proceed much in solving this question.
Point A moves with constant velocity v so that the vector v is continually pointed towards the point B which in turn is in a rectilinear motion with a uniform velocity u < v. at the initial moment of time vector v is perpendicular to the vector u and the points are separated by a distance of l. how soon the points will converge?

The problem that I face with this problem is that there is no definition of when does A start turning and what will be the direction and the distance between A and B when A starts turning. In fact A turns constantly(I know that).
 
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A starts turning when B is moving. Remember, the vector v is always pointing from A to B, and B is moving with speed u.

I can think of the case where v is the constant velocity on a circular arc of radius l.

v and u are uniform. Also, v2= vx2(t) + vy2(t)

In order to meet, pt A and B, must traverse the same distance in the same time, so <vy> = u during the same period.
 
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Let u is along x
at time t, v makes theeta with u

1. in time interval t the relative distance covered in x direction is zero

2 in time interval t distance covered by A relative to B along AB = l

the tric is in integrals

try a good question!

Dont see the back of I.E. Erodov

MP
 
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