A doctor has prescribed a corrective lens of power, -1.5D. Find the focal length of the lens. Is the prescribed lens diverging or converging?
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$\text{P}=-1.5\text{D}$$\text{P}=\frac{1}{\text{f}}$
$\text{f}=\frac{1}{\text{P}}=\frac{1}{(-0.5)}=-0.66\text{m}=-66.6\text{m}$
Since focal length is negative, it is a diverging lens.
$\text{f}=\frac{1}{\text{P}}=\frac{1}{(-0.5)}=-0.66\text{m}=-66.6\text{m}$
Since focal length is negative, it is a diverging lens.
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