Question

An unbanked curve has a radius of $60m$. Coefficient of friction between the tyre of truck and road is $0.75$. The distance between two front wheel of truck is $2m$. If the truck exceeds the speed of safe limit, then select the correct statement and justify your asnwer.
1) Inner wheels leave the ground first.
2) Outer wheels leave the ground first.

Answer 1

While turning the maximum allowed speed is:

$V_{max}=\sqrt{\mu rg}$

where,

$\mu$ is coefficient of friction,

$r$ is radius of the turn and

$g$ acceleration due to gravity.

Since the inner wheels are closed to the centre of the curve. Therefore, $V_{max}$ is lower for inner wheel than for the outer wheel. Thus the inner wheel leaves the ground first.