Physicshard · Past Paper
Which of the following describes the 'f-number' of a camera?
AFocal length / Aperture diameter
BAperture diameter / Focal length
CFocal length * Aperture
D1 / Focal length
✓ Correct Answer: A — Focal length / Aperture diameter
The f-number (focal ratio) is the ratio of the lens's focal length to the diameter of the entrance pupil.
Share this question
More from Physics
- What is the shape of the wavefront for light coming from a very distant star?
- Which of the following correctly relates frequency (f), wavelength (L), and speed (v)?
- The distance x of a particle varies with time t as x = at^2 - bt^3. The acceleration of the particle will be zero at time t equals to:
- What is the relationship between density (d), mass (m) and volume (v)?
- Hydrometer is an instrument used to measure: