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If this speed is based on what would be safe in wet weather, estimate the radius of curvature for a curve marked 45 km/hkm/h . The coefficient of static friction of rubber on wet concrete is μs=0.7μs=0.7, the coefficient of kinetic friction of rubber on wet concrete is μk=0.5μk=0.5

User Don H
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1 Answer

7 votes

Answer:

r = 22.78 m

Step-by-step explanation:

For this exercise let's use Newton's second law

Axis y

N- W = 0

N = W

X axis

F = m a

Where the acceleration is centripetal

a = v² / r

The force is the friction that the formula has

fr = μ N

fr = μ mg

Let's replace

μ m g = m v² / r

r = v² / μ g

Let's reduce the speed to the SI system

v = 45 km / h (1000 m / 1 km) (1h / 3600 s) = 12.5 m / s

r = 12.5 2 / (0.7 9.8)

r = 22.78 m

User Hettie
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