MCQ
The graph shows how the magnification $m$ produced by a thin lens varies with image distance $v$. What is the focal length of the lens used?
- A$\frac {b^2}{ac}$
- B$\frac {a}{c}$
- C$\frac {b^2c}{a}$
- ✓$\frac {b}{c}$
✓
Answer
Correct option: D.
$\frac {b}{c}$
d
$f\,=\,\frac {b}{c}$
$f\,=\,\frac {b}{c}$
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