GATE 2026 AR — Planning – Question 55

Urban Land Use and Transportation · Traffic survey methods, Traffic flow Analysis · 1 mark · Numerical answer

A Greenshields speed-density model is v=75−0.03k, with v in km/hour and k in vehicles/km. Find jam density in vehicles/km, as an integer.

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Correct answer: 2500 to 2500

Explanation

Jam density occurs when mean speed falls to zero. Set 0=75−0.03k, giving k=75/0.03=2500 vehicles/km. The 75 coefficient is the free-flow speed; the density intercept is obtained from the zero-speed condition.

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