Find the maximum speed at which a car can turn round a curve of `30 m` radius on a level road if coefficient of friction between the tyress and road is `0.4. Take g = 10 m//s^(2)`.

Explanation

Here, `upsilon_(max) = ?, r = 30m, mu = 0.4`
`g = 10 m//s^(2)`
on a level road, centripetal force is provided by force of friction between the tyres and road.
i.e., `f gt (m upsilon^(2))/(r ) or (m upsilon^(2))/(r ) lt f (= mu R = mu mg)`
`:. upsilon_(max) = sqrt(mu rg) = sqrt(0.4 xx 30 xx 10)`
`= sqrt(120) = 11 m//s`