A compound microscope has an objective of focal length 2cm and an eye-piece of focal length 5 cm. If an object is placed at a distance of 2.4 cm in front of the field lens, find the magnifying power of the instrument and length of the tube if
(a) final image is at infinity
(b) final image is at least distance of distinct vision (=25cm).

Explanation

To solve the problem step by step, we will first analyze the given data and then apply the relevant formulas for a compound microscope.

### Given Data:
- Focal length of the objective lens, \( f_o = 2 \, \text{cm} \)
- Focal length of the eyepiece lens, \( f_e = 5 \, \text{cm} \)
- Object distance from the objective lens, \( u_o = -2.4 \, \text{cm} \) (negative as per sign convention)

### Step 1: Find the image distance for the objective lens (\( v_o \))
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