A car rounds a flat curve of radius 50 m with a constant speed of 20 m/s. What is the minimum coefficient of static friction between the tires and road that allows the car to make the turn without slipping?

Core Concept

For a car rounding a flat curve, the centripetal force is provided by friction: f = mv²/r. The maximum static friction is f_max = μ_s mg. Setting these equal: μ_s mg = mv²/r, so μ_s = v²/(rg) = (20)²/(50×9.8) ≈ 0.816. Option A is incorrect as it's too low, possibly using half the correct value. Option B is incorrect as it's approximately half the correct value. Option C is incorrect as it's approximately 3/4 of the correct value.