A tower 100m tall at a distance of 3km is seen through a telescope having objective of focal length 140cm and eyepiece of focal length 5cm. What is the size of final image if it is at 25cm from the eye?

Explanation

To solve the problem, we will follow these steps:

### Step 1: Convert the height and distance of the tower into consistent units
- The height of the tower \( H = 100 \, \text{m} = 10000 \, \text{cm} \)
- The distance from the telescope to the tower \( D = 3 \, \text{km} = 300000 \, \text{cm} \)

### Step 2: Use the lens formula for the objective lens
The lens formula is given by:
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