A rail road curve is to be laid out on a circle. What radius should be used if the track is to change direction by 25`degree` in a distance of `40m e t r e s` ?

Explanation

We know, length of the arc ` = r*theta`

Here, `theta` is in radians.

`:. 40 = r*25(pi/180)`

`=> r = (40*180)/(25pi) = 288/pi = 91.6m`

So, the required radius is `91.6m.`