Question

A digital camera with a focal length of 150 mm is flown at a height of 3000 m over a flat terrain for taking aerial photographs. The scale of the aerial photograph is 1: ________. [in integer]

Hint:

The scale of an aerial photograph can be found by dividing the focal length by the height of the camera above the ground.

Answer 1

Correct Answer: 20000

The scale of an aerial photograph is given by the ratio of the focal length of the camera to the height of the camera above the ground. The formula for scale \( S \) is: \[ S = \frac{\text{focal length}}{\text{height}} = \frac{150 \, \text{mm}}{3000 \, \text{m}} = \frac{150 \times 10^{-3} \, \text{m}}{3000 \, \text{m}} = \frac{150}{3000000} = 1:20000 \] Thus, the scale of the aerial photograph is \( \boxed{20000} \).