JEE Mains · Physics · STD 12 - 9. Ray optics and optical instruments
A photograph of a landscape is captured by a drone camera at a height of 18 km . The size of the camera film is \(2 \mathrm{~cm} \times 2 \mathrm{~cm}\) and the area of the landscape photographed is \(400 \mathrm{~km}^2\). The focal length of the lens in the drone camera is :
- A 1.8 cm
- B 0.9 cm
- C 2.8 cm
- D 2.5 cm
Answer & Solution
Correct Answer
(A) 1.8 cm
Step-by-step Solution
Detailed explanation
\(\mathrm{H}=18 \mathrm{~km}\) Size of camera film \(=2 \mathrm{~cm} \times 2 \mathrm{~cm}\)…
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