The safe speed of a vehicle over a smooth banked road of radius $150\ m$ is $10\ m/s$. If the width of the road is $7.5\ m$,the height of the outer edge is: (in $m$)

The radius of a curved road on a national highway is $R$. The width of the road is $b$. The outer edge of the road is raised by $h$ with respect to the inner edge so that a car with velocity $v$ can pass safely over it. The value of $h$ is

$A$ road is banked at an angle of $30^o$ to the horizontal for negotiating a curve of radius $10\sqrt{3} \ m$. At what velocity will a car experience no friction while negotiating the curve? ............... $km/hr$

$A$ lorry is moving on a smooth circular path of radius $50 \ m$ with a velocity of $20 \ ms^{-1}$. Then the banking angle of the road is (Acceleration due to gravity $= 10 \ ms^{-2}$)

$A$ railway track is banked for a speed $v$ by elevating the outer rail by a height $h$ above the inner rail. If the distance between the two rails is $d$,then the radius of curvature of the track is ($g$ = gravitational acceleration).

Define optimum speed.