Grade 12Mechanics

The driver of a blue car moving at a speed of 80km/h, suddenly realizes that she is about to rear-end a red car, moving at a speed of 60km/h.To avoid a collision, what is the maximum speed the blue can have just as it reaches the red car ? (Please do not use the concept of relative motion to solve this problem:)
Thanks !

Ashish Ranjan

10 Years agoGrade 12

5 Answers

Vikas TU

10 Years ago

Let v be the speed required to avoid collision.

Now relativee speed with rear end car should not be poitive.

.i.e

v – 60

Vikas TU

10 Years ago

Let v be the speed required to avoid collision.

Now relativee speed with rear end car should not be poitive.

.i.e

v – 60

= 60 km/hr. (maximum)

Ashish Ranjan

10 Years ago

am i right please check Vikashrelative speed with respect to rear end of car Red should not be positive.

Ashish Ranjan

10 Years ago

relative speed of blue car with respect to rear end of car Red should not be positive.

SORRY FOR INCONVINIENCE !!!

Vikas TU

10 Years ago

Yes, Ashish

U r right!

relative speed of blue car with respect to rear end of car Red should not be positive.

whatever i answered earlier that is.

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Ashish Ranjan

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