Question

two cars A and B are approaching Each Other head on with speed 20 metre per second and 10 metre per second respectively then there's equation is X then A and B start breaking at 4 metre per second square into metre per second square respectively minimum value of x to avoid collision is​

Answer 1

minimum separation = sum of stoping distance of two cars

Car- A :

u = 20 m/s

a = - 4 m/sq-sec

s = (v^2 - u^2) / 2a = - 20×20 / (- 2 × 4) = 50 m

stoping distance = 50 m

Car- B :

u = 10 m/s

a = - 2 m/sq-sec

s = - 10×10 / (- 2×2) = 25 m

stoping distance = 25 m

so,

minimum value of -

x = 50 + 25 = 75 m