Find the Power of a Bi Convex Lens

[Deebu R]

Homework Statement

If the focal length of the bi convex lens is 25 cm then the power of the lens will be?
Since the light striking the lens converges at a point behind the lens will the answer come in positive?

Homework Equations

Power of lens D= 1/f

The Attempt at a Solution

D= 1/25= +0.04 dioptre[/B]

 

[rude man]

You are using the wrong units in your formula.

 

[Deebu R]

You are using the wrong units in your formula.

Focal length should be in mm?

 

[Deebu R]

Or is it meters? Is the answer +4 diopter?

 

[BvU]

Correct

 

[Deebu R]

I see.Thank you for the help rude man and BvU.