Let a chase b, a speed v 1, b speed v2. A time t 1, b time t2. V 1t 1-v2t2= distance difference (because t 1=t2 is the catch-up time).

Catch-up time = distance difference divided by (v 1-v2)

Namely: catch-up time = distance difference divided by speed difference.

The chasing and meeting problems involved in the movement of two objects on the same straight line or closed figure are usually classified as chasing problems. This kind is often found in exams. Generally, it can be divided into two types: one is that two people chase and two people meet, which is relatively simple; One is that it is more difficult for many people to catch up and meet.

Extended data:

The conventional method to solve the tracing problem is to list the equations according to the displacement equation. The displacement formula of uniform linear motion is a quadratic equation, so the quadratic trinomial (y=ax? +bx+c) (the properties and discriminant of △ = b? -4ac).

In addition, when two (or several) objects are moving, one of them is often taken as the reference, that is, only the other (or several) objects are moving to make them "stationary". This simplifies the research process, so the problem of traceability is often solved by changing the reference method. At this time, the initial velocity and acceleration of other objects relative to the reference object should be determined before the motion of other objects can be determined.

References:

Baidu Encyclopedia-Tracking Problems