A standard biological microscope is required to have amagnification of 200.

1)When paired with a 10 eyepiece, what power objective isneeded to get this magnification? Assume that the length of thetube of a standard biological microscope is 15 .

2) What is the focal length of the objective?

1. 20.0

1- M_o=200x/10x=20

85

To calculate the power objective needed to achieve a magnification of 200 when paired with a 10 eyepiece, you can use the formula for the total magnification of a compound microscope:

Total magnification = Power objective x Power eyepiece

Given that the eyepiece power is 10 and the desired total magnification is 200, we can rearrange the formula to solve for the power objective:

Power objective = Total magnification / Power eyepiece

Substituting the values, we get:

Power objective = 200 / 10 = 20

Therefore, the power objective needed to achieve a magnification of 200 when paired with a 10 eyepiece is 20.

Now, to find the focal length of the objective, we can use another formula:

Power objective = 1 / focal length (in meters)

Rearranging the formula to solve for the focal length:

focal length = 1 / Power objective

Substituting the value we found for the power objective:

focal length = 1 / 20 = 0.05 meters (or 50 mm)

Therefore, the focal length of the objective is 0.05 meters (or 50 mm).