Question

A curve has a radius of 50 meters and a banking angle of 15. What is the ideal, or critical, speed (the speed for which no friction is required between the car's tires and the surface) for a car on this curve?

• A. 20 m/s
• B. 5 m/s
• C. 11 m/s
• D. 25 m/s

Answer 1

The correct option is C 11 m/s

Here, radius of curve, $r=50m$ and banking angle, $\theta ={15}^{\circ }$
We have to find out the ideal speed v (the speed for which no friction is required between the car's tires and the surface)
we know that the critical speed for an automobile without overturning in the absence of friction is given by $v=\sqrt{rgtan\theta }=\sqrt{50\times 9.8\times tan15}=11m/s$
If the car has a speed of about 11 m/s, it can negotiate the curve without any friction.
The correct option is (c)