MCQ
Amount of light entering into the camera depends upon
- AFocal length of the objective lens
- BProduct of focal length and diameter of the objective lens
- CDistance of the object from camera
- ✓Aperture setting of the camera
✓
Answer
Correct option: D.
Aperture setting of the camera
d
(d) An aperture is an hole through which light light enters the camera, if $N$ is the f-number, $f$ is focal length and $D$ the diameter of hole then amount of light entering into the camera is proportional aperture area.
(d) An aperture is an hole through which light light enters the camera, if $N$ is the f-number, $f$ is focal length and $D$ the diameter of hole then amount of light entering into the camera is proportional aperture area.
Area $=\frac{\pi D^{2}}{4}=\pi\left(\frac{f}{2 N}\right)^{2}$
Thus option $D$ is correct.
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