You are using a microscope with a 10X025 25X050 45X080 and 9

You are using a microscope with a 10X/0.25, 25X/0.50, 45X/0.80 and 90X/1.30 objective lenses and a 10X ocular lens (these are listed as magnification/numerical aperture). The condenser numerical aperture is 1.5. The wavelength of light being used is 750nm. What is the lowest magnification that will allow you to see two cells as separate that are 400nm apart? Write the equation(s) you will use, fill them in and then answer.

Solution

Please find the answer below:

The given magnifications of objective lenses are: 10X/0.25X, 25X/0.5X, 45X/0.8X and 90X/1.3X.

Magnification of eye-piece:10X

Numerical aperture of the condenser, na = 1.5

Wavelength of incident light, w = 750nm

Distance between two cells: 400 nm.

The resolution (R) of a microscope is given by:

R = 1.22 (w) / na

Here, we can put the values: R = (1.22 * 750)/1.5 or 610.

Thus, the resolution produced by the microscope would be 610 nm. It can be seen from the equation above that the resolution produced by the microscope is independent of the magnification of the lenses. This suggests that since the minimum resolution produced by microscope is 610 nm and the cells are placed 400 nm apart, the microscope will be able to visualize these two cells as separate at any magnification.