A microscope has an objective lens of focal length 1.40 mm and an eyepiece of focal length 20.00 mm. It is adjusted for minimum eyestrain for persons with a near point of 25.0 cm. A blood sample is placed 1.50 mm from the objective. The magnitude of the overall magnification is closest to 102) 180. 37. 370. 18. 103)A compound microscope has an objective with a focal length of 3.00 mm and an eyepiece of focal length 6.00 cm. It is adjusted for minimum eyestrain for persons with a near point of 25 cm. If the two lenses are separated by 40.0 cm, what is the total overall magnification

(a). The overall magnification is 175.

(b). The overall magnification is 472.

Explanation:

Given that,

Focal length of lens = 1.40 mm

Focal length of eyepiece = 20.00 mm

Near point  = 25.0 cm

Object distance = 1.50 mm

(a). We need to calculate the image distance

Using formula of lens

Put the value into the formula

We need to calculate the magnification of objective lens

Using formula of magnification

Put the value into the formula

We need to calculate the length

Using formula for length

Put the value into the formula

We need to calculate the overall magnification

Using formula of magnification

Put the value into the formula

The overall magnification is 175.

(b). Focal length = 3.00 mm

Focal length of eyepiece = 6.0

Near point = 25 cm

Length = 40.0 cm

We need to calculate the overall magnification

Using formula of magnification

Put the value into the formula

Hence, (a). The overall magnification is 175.

(b). The overall magnification is 472.