Question

A camera equipped with a focal length of 150mm is used to take a vertical photograph from a flying height of 2750m above mean sea level. If the terrain is flat and located at an elevation of 500m above mean sea level, the scale of the photograph will be:

• A. \(\text{1:1500} \)
• B. \(\text{1:1833} \)
• C. \(\text{1:15000} \)
• D. \(\text{1:18330} \)

Hint:

The scale of an aerial photograph is determined by focal length and flying height using the formula \(S = \frac {f}  {H - h}\).

Answer 1

The Correct Option is C

Step 1: Understanding the scale formula for aerial photographs. The scale of a vertical aerial photograph is given by: 

\[S = \frac {f}  {H - h}\]

 where: - \( f = 150mm = 0.150m \) (focal length), - \( H = 2750m \) (flying height), - \( h = 500m \) (terrain elevation). 
Step 2: Calculating the scale.  \(S = \frac{0.150} {2750 - 500}\)  

\(= \frac{0.150} {2250}   \)

\(S = 1:15000 \)

Step 3: Selecting the correct option. Since the computed scale is 1:15000, the correct answer is c. 1:15000.