Question
Write the lens formula explaining the meaning of the symbols used.
✓
Answer
Lens formula :
$
\frac{1}{ v }-\frac{1}{ u }=\frac{1}{ f }
$
The distance of the object from the optical centre is called the object distance $(u)$.
The distance of the image from the optical centre is called the image distance (v).
The distance of the principal focus from the optical centre is called the focal length (f).
$
\frac{1}{ v }-\frac{1}{ u }=\frac{1}{ f }
$
The distance of the object from the optical centre is called the object distance $(u)$.
The distance of the image from the optical centre is called the image distance (v).
The distance of the principal focus from the optical centre is called the focal length (f).
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