Biology - Calculating Resolving Power of Microscope?

[ummyster]

Biology -- Calculating Resolving Power of Microscope??

Homework Statement

The question is this:

Resolving power is a function of the wavelength of light used and the numerical aperature of the objective lens. Given that RP= wavelength / (2 x NA), calculate the resolving power of the microscope when using oil immersion lens. Visible light has an average wavelength of 0.55 um ( 1 um = 0.000001 meters)

:/ Help? I think I got it but I'm not sure what to use for NA.

Homework Equations

RP= wavelength / (2 x NA)

The Attempt at a Solution

RP= (0.55 um x 0.000001 meters) / (2 x 1.3 )

I found that 1.3 value online. I don't even understand how to get that value...

 

[mgb_phys]

The numerical aperture depends on the focal length of the objective (and it's design)
Were you given the magnification?

 

[chemisttree]

http://www.microscopy.fsu.edu/primer/anatomy/numaperture.html