When is magnification positive or negative ?

In cyclic processes, when is the work done positive or negative?

What is meant by power of a lens ? When is it positive or negative? Define one dioptre.

Positive And Negative Work

When the intensity of magnetisation is said to be positive or negativE?

What is a positive and a negative ion?

The linear magnification of a concave mirror can be positive or negative. Why?

When temperature gradient is considered as positive and negative ?

Considering the correlation between the word of the first pair , pair of third word accordingly with proper answer OR write the correlated answer: Magnification positive : Erect image :: Magnification negative : ……………….