Two cars are facing each other from opposite ends of a 500m long road. Car A begins travelling at a constant speed of 20m/s. At the same moment, Car B begins travelling toward Car A at a constant speed of 16m/s. How far will Car A move before colliding with Car B?

Correct  D₁ = 277.78 m  

Explanation:

Before colliding  with car B, car A will cross the next distance:

D₁ = V₁ t  

Before colliding  with car A, car B will cross the next distance:

D₂ = V₂ t

The total distance is:

D = D₁ + D₂  => D = V₁ t + V₂ t  => D = t (V₁ + V₂) => t = D / (V₁ + V₂)

t = 500 / (20 + 16) = 500 / 36 = 13.89 seconds

D₁ =  V₁ t  = 20 · 13.89 = 277.78 m

D₁ =  277.78 m

God is with you!!!

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