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A curve of radius 72 m is banked for a design speed of 100 km/h If the coefficient of static friction is 0.31 (wet pavement), at what range of speeds can a car safely make the curve?

User Qinmiao
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4 votes

Final answer:

The range of speeds can a car safely make the curve, the ideal speed to take the banked curve is approximately 25.41 m/s and the coefficient of static friction needs to be greater than or equal to approximately 0.27 for the car to safely make the curve at any speed.

Step-by-step explanation:

When a car takes a banked curve, the force of gravity and the normal force combine to provide the centripetal force required to keep the car moving in a circular path. The ideal speed to take a banked curve can be calculated using the formula:

ideal speed = √(g * r * tanθ)

where

g is the acceleration due to gravity (9.8 m/s^2)

r is the radius of the curve (72 m)

θ is the angle of banking (given as 15.0°).

Plugging in these values, we get:

ideal speed = √(9.8 * 72 * tan(15.0°)) ≈ 25.41 m/s.

The minimum coefficient of static friction needed for a car to safely make the curve at a particular speed can be calculated using the formula:

μ = tanθ

where

μ is the coefficient of static friction

θ is the angle of banking.

Plugging in the given angle of banking (15.0°), we get:

μ = tan(15.0°) ≈ 0.27.

Therefore, for a car to safely make the curve, it should be driven at a range of speeds less than or equal to approximately 25.41 m/s and the coefficient of static friction should be greater than or equal to approximately 0.27.

User Trebor Rude
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