An astronomical telescope has `f_(o)= 200 cm` and `f_(epsilon) = 4cm`. Telescope is focused to see an object 10 km from the objective. Final image is formed at infinity. Find length L of the tube and the angular magnification of telescope.

Explanation

To solve the problem step by step, we need to find the length of the tube (L) of the telescope and the angular magnification (M) of the telescope.

### Step 1: Understanding the Given Data
- Focal length of the objective lens, \( f_o = 200 \, \text{cm} \)
- Focal length of the eyepiece lens, \( f_e = 4 \, \text{cm} \)
- Distance of the object from the objective lens, \( d_o = 10 \, \text{km} = 1000 \, \text{m} = 100000 \, \text{cm} \)
- The final image is formed at infinity.

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