- #1
walking
- 73
- 8
Am I right in thinking the 680J thing is a red herring? Even using the author's method of "same work required in either case" (ie =mgh in both cases) we still end up cancelling h and getting $$F=\frac{mg\sin \theta}{\cos \phi}\ge mg\sin \theta=320$$ etc. I.e. no need for 680J. Maybe I am wrong?