Dear Student ,
u is object distance
v is image distance
f is focal length
h is height of object
h' is height of image
m is magnification
Above quantities are applied for all mirrors and lens.
Sign convention of mirror
1. Concave mirror
u = negative
v = negative (Real and Inverted) and positive (Virtual and Erect)
f = negative
h = positive
h' = negative (Real and Inverted) and positive (Virtual and Erect)
m = negative (Real and Inverted) and positive (Virtual and Erect)
2. Convex Mirror
u = negative
v = positive
f = positive
h = positive
h' = positive
m = positive
Regards