Question

Camera lenses are described in terms of

Answer 1

Answer:

The position of the image from the camera lens is approximately 121.1 mm

Explanation:

The given parameters of the lens are;

The specification of the camera lens = 120 mm

Therefore, the focal length of the camera lens, f = 120 mm = 0.12 m

The distance of the object from the camera, $d_o$ = 13 m

The lens equation for finding the position of the image is given as follows;

$\dfrac{1}{f} = \dfrac{1}{d_o} + \dfrac{1}{d_i}$

Where;

$d_i$ = The position of the image from the camera lens

Therefore, by plugging in the known values, we have;

$\dfrac{1}{13} = \dfrac{1}{0.12} + \dfrac{1}{d_i}$

$\dfrac{1}{d_i} = \dfrac{1}{0.12} - \dfrac{1}{13} = \dfrac{13 - 0.12}{0.12 \times 13} = \dfrac{12.88}{1.56} = \dfrac{322}{39}$

$\therefore d_i = \dfrac{39}{322} \approx 0.1211$

The position of the image from the camera lens, $d_i$ = 0.1211 m = 121.1 mm