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en/13.1.17.md
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| + | ### Statement | ||
| + | |||
| + | $13.1.17.$ [Insert the problem statement] | ||
| + | |||
| + | ### Solution | ||
| + | |||
| + | Firstly, the magnification of the object is given by:\ | ||
| + | $k = \frac{s'}{s}$ (1)\ | ||
| + | where $s'$ is the image-mirror distance and $s$ is the object-mirror distance, with $k$ = 3.\ | ||
| + | And the relation for these distances is\ | ||
| + | $\frac{1}{s} +\frac{1}{s'} = \frac{1}{f}$ (2)\ | ||
| + | When object is moved a distance $d$ away from the mirror, the magnification changes\ | ||
| + | $m = \frac{s''}{s+d}$ (3)\ | ||
| + | with $m$ = 0.5.\ | ||
| + | And the relation for these distances is\ | ||
| + | $\frac{1}{s+d}+\frac{1}{s''}=\frac{1}{f}$ (4)\ | ||
| + | From (1) and (2), eliminating term $s'$,\ | ||
| + | $\frac{s}{f} = 1+\frac{1}{k}$ (5)\ | ||
| + | From (3) and (4), eliminating term $s''$, | ||
| + | $\frac{s}{f}=1+\frac{1}{m}-\frac{d}{f}$ (6)\ | ||
| + | Equaling (5) and (6), and separating $f$,\ | ||
| + | $f = \frac{mkd}{k-m} = 48\;\rm{cm}$ | ||
| + | |||
| + | |||
| + | #### Answer | ||
| + | |||
| + | [Insert a concise answer or boxed result] | ||
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| ### Statement | |||
| $13.1.17.$ [Insert the problem statement] | |||
| ### Solution | |||
| Firstly, the magnification of the object is given by:\ | |||
| $k = \frac{s'}{s}$ (1)\ | |||
| where $s'$ is the image-mirror distance and $s$ is the object-mirror distance, with $k$ = 3.\ | |||
| And the relation for these distances is\ | |||
| $\frac{1}{s} +\frac{1}{s'} = \frac{1}{f}$ (2)\ | |||
| When object is moved a distance $d$ away from the mirror, the magnification changes\ | |||
| $m = \frac{s''}{s+d}$ (3)\ | |||
| with $m$ = 0.5.\ | |||
| And the relation for these distances is\ | |||
| $\frac{1}{s+d}+\frac{1}{s''}=\frac{1}{f}$ (4)\ | |||
| From (1) and (2), eliminating term $s'$,\ | |||
| $\frac{s}{f} = 1+\frac{1}{k}$ (5)\ | |||
| From (3) and (4), eliminating term $s''$, | |||
| $\frac{s}{f}=1+\frac{1}{m}-\frac{d}{f}$ (6)\ | |||
| Equaling (5) and (6), and separating $f$,\ | |||
| $f = \frac{mkd}{k-m} = 48\;\rm{cm}$ | |||
| #### Answer | |||
| [Insert a concise answer or boxed result] | |||