For a body moving in a circular path,what is the condition for no skidding if $\mu$ is the coefficient of friction?

$A$ disc rotates about its axis of symmetry in a horizontal plane at a steady rate of $3.5$ revolutions per second. $A$ coin placed at a distance of $1.25\,cm$ from the axis of rotation remains at rest on the disc. Find the coefficient of friction between the coin and the disc. (Take $g = 10\,m/s^2$)

$A$ car moving on a horizontal road may be thrown out of the road when taking a turn due to:

$A$ circular road of radius $1000 \, m$ has a banking angle of $45^\circ$. The maximum safe speed of a car having mass $2000 \, kg$ will be,if the coefficient of friction between the tyre and road is $0.5$,equal to ....... $m/s$.

An unbanked curve has a radius of $60\,m$. The maximum speed at which a car can make a turn if the coefficient of static friction is $0.75$,is ........ $m/s$.

The maximum safe speed of a car on a horizontal road with a radius of $500\,m$ and a coefficient of friction of $0.5$ is ...... $m/s$.