What is the value of the focal length fn2

of a convergent lens with index of refraction ( n2 =1.5) if it was
fn1 =5cm for an index of refraction n1 = 1.4

To calculate the value of the focal length f(n2) of a convergent lens with an index of refraction n2, given that the focal length f(n1) for an index of refraction n1 is known, we can use the lensmaker's formula.

The lensmaker's formula relates the focal length of a lens to the curvature of its surfaces and the refractive indices of the lens materials. It is given by:

1/f = (n2 - n1) * (1/R1 - 1/R2)

Where:
- f is the focal length of the lens
- n1 and n2 are the refractive indices of the lens material and the surrounding medium, respectively
- R1 and R2 are the radii of curvature of the two lens surfaces

In this case, we are given the focal length f(n1) = 5 cm for an index of refraction n1 = 1.4 and the index of refraction n2 = 1.5. However, the radii of curvature are not provided. Without the radii of curvature, it is not possible to determine the value of f(n2) precisely using the lensmaker's formula.

To find the exact value of f(n2), we would need either the radii of curvature or another piece of information about the lens. If we have additional information, please provide it, and I'll be happy to assist you further.