A toy train moves around a circular track of radius $0.80 \text{ m}$. How many radians has the train turned through in moving $2.2 \text{ m}$ along the track?"
I'm not sure how to work out how many radians the train has turned is there a specific equation for this ?
The given radius $0.80$ metres and the train has turned $2.2m$.
This situation is similar to that of:
Length of arc= $2.2m$ and Radius= $0.80m$.
The angle in radian, length of arc and radius are related as (I think it is known to you):
$\theta=$length of arc/radius.
So angle in radians=$\theta$=$2.2/0.8$=$11/4 radians$