A disc rotates about its axis of symmetry in a hoizontal 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. The coefficient of friction between the coin and the disc is $(g\, = 10\,m/s^2)$
$0.5$
$0.7$
$0.3$
$0.6$
The maximum speed that can be achieved without skidding by a car on a circular unbanked road of radius $R$ and coefficient of static friction $\mu $, is
Radius of the curved road on national highway is $R$. Width of the road is $b$. The outer edge of the road is raised by $h$ with respect to inner edge so that a car with velocity $v$ can pass safe over it. The value of $h$ is
A car is moving on a horizontal circular road of radius $0.1 \,km$ with constant speed. If coefficient of friction between tyres of car and road is $0.4$, then speed of car may be ......... $m / s$ $\left(g=10 \,m / s ^2\right)$
A car is moving on a horizontal circular track of radius $0.2 \,km$ with a constant speed. If coefficient of friction between tyres of car and road is $0.45$, then speed of car may be ........ $m / s$ [Take $g=10 \,m / s ^2$ ]
Write the formula for the maximum permissible speed of a vehicle moving on smooth circular balanced tracks.