I have the following question before me:
Principal normal of a curve in space will be binormal of another curve if the curvature of given curve is proportional to $k^2+z^2$
Can anyone help me regarding this question as to what is the meaning of $k$ here? To add context to this problem, this problem appeared in this year's Indian Forest Service examination wherein they did not mention what $k$ was. I think $k$ here is referring to the curvature of another curve.
Please help.