Two cars A and B are travelling in same direction with speed v_{1 }and v_{2 }respectively (v_{1 >} v_{2} ). When car A is d distance behind the car B, the brakes on A are applied, causing retardation . Show that to prevent a collision between A and B it is necessary that

(v_{1 >} v_{2} )^{2} < (2d)

### Asked by Topperlearning User | 4th Jun, 2014, 01:23: PM

Here, in problem to prevent the collision of car A with B, the relative velocity of car A w.r.t. B should reduce to zero before car A undergoes the relative displacement of d w.r.t. car B.

### Answered by | 4th Jun, 2014, 03:23: PM

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