A circular curve of a highway is designed for traffic moving at `72kmh^(-1)`. If the radius of the curved path is 100 m, the correct angle of banking of the road should be

Options

A. `tan^(-1).(2)/(3)`
B. `tan^(-1).(3)/(5)`
C. `tan^(-1).(2)/(5)`
D. `tan^(-1).(1)/(4)`

Answer

C

Explanation

`V=sqrt(gR tan theta)rArr (20)^(2)=10xx100xx tan theta`
`rArr tan theta=4/10=2/5rArr theta=tan^(-1) (2//5)`