Is the Focal Point of a Concave Mirror Always Positive?

[afcwestwarrior]

I know that when the focal point is in the inside of a concave mirror. The focal point is greater than zero, and the radius is greater than zero and the lateral magnification is greater than zero.

So if the focal point is on the outside of this concave mirror. Would the focal point be less than zero, and would the radius be less than zero, and would the lateral magnification be less than zero.

 

[mgb_phys]

Sorry not sure what you mean, the focal length of a concave mirror is half the radius of curvature.

see http://www.glenbrook.k12.il.us/GBSSCI/PHYS/class/refln/u13l3a.html