Question

for class 10th .... positive and negative signs for f,v,u....for lens which we are applying in problems in light lesson??

Answer 1

for mirrors
concave mirror ----    f-negative       u=negative   v- negative   ( positive when the object is between P and F.)
convex mirror---------   f-positive     u--negative       v-positive.

for lenses
 convex lens-----f--positive   u-negative     v-positive  (negative when the object is in between O and F1)
concave lens-------- f- negative    u- negative     v- negative

Answer 2

Explanation:

positive and negative