A vehicle is travelling with a design speed of 90 kmph on a horizontal curve of radius 300 m and the coefficient of lateral friction is considered as 0.15. What is the superelevation if full lateral friction is assumed to be developed? (Assume plain and rolling terrain)
- A0.0526
- B0.0626Correct
- C0.07
- D0.1
Solution
Concept
Superelevation
Formula
e + f = V²/127R
Step-by-step solution
1. e + 0.15 = 90²/(127 × 300) = 0.2126. 2. e = 0.0626.
Explanation
Friction is fully developed.
Why the other options are wrong
Others do not follow.
Shortcut
e = V²/127R − f.
Correct answer: B) 0.0626