Question

can u tell me how i can take sign conversation in science, physics ,10th light reflection and refraction​

Answer 1

In case of focal length -

Convex(mirror and lens) - Positive

Concave(mirror and lens) - Negative

In case of magnification -

Positive - Virtual and erect image

Negative-Real and inverted image

U(object distance) is always negative

Hope it helps u

Answer 2

u is always positive

f is neg for concave nd positive for convex

v depends on the image which is formed

for real v is positive nd for virtual it is negative