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## Is V positive for convex lens?

‘**v’ is always positive for convex** mirror & concave lens. Distances measured from the optic center to the right of the lens are considered +ve and t from optic center to the left are -ve.

## What is the sign of V in convex and concave lens?

And for image distance, V in lens it **is taken as positive in Convex lens** since image is formed on +X side. It is taken as negative in Concave lens since image is formed in -X side of the Cartesian. In Concave mirror V is taken as positive and negative for convex mirror.

## Is convex lens V negative?

And for image distance, V in lens it is taken as positive in Convex lens since image is formed on +X side. It is taken as **negative** in Concave lens since image is formed in -X side of the Cartesian. In Concave mirror V is taken as positive and negative for convex mirror.

## How do you know if V is positive or negative?

In case of a concave lens ‘**v’ is always negative**. In case of convex lens it is negative or positive it depends on object distance n location.

## In which mirror V is negative or positive?

For example, in the case of convex mirrors, always virtual images are formed behind the mirror. When the object is on the left side of the mirror, image is on the right side of the mirror. Hence u **is negative and v is positive**.

## What is the sign of U V and f for a convex lens according to Cartesian sign convention?

See according to the New Cartesian Sign convention U i.e., the object distance is always in the left hand side of the lens or mirror i.e., to -X side. That is why **U is always taken as negative**. For focal length, f in lens is always taken as negative for concave and positive for convex.

## How do you know if a lens is concave or convex?

**A convex lens is thicker at the centre and thinner at the edges**. A concave lens is thicker at the edges and thinner at the centre. Due to the converging rays, it is called a converging lens. Due to the diverging rays, it is called a diverging lens.

## Is focal length of convex lens positive or negative?

The focal length of a concave surface is negative, whereas the focal length of a convex surface **is positive**. Therefore, for a lens, the power of a concave and convex lens is negative and positive respectively.