Question

An object is placed at a distance of $5$ cm from a convex lens of focal length $10$ cm, then the image

• A. -10
• B. -20
• C. -30
• D. -40

Answer 1

The correct option is A -10

We know from lens formula

$\frac{1}{v}-\frac{1}{u}=\frac{1}{f}$

$\frac{1}{v}=\frac{1}{f}+\frac{1}{u}$

$\frac{1}{v}=\frac{1}{10}-\frac{1}{5}$

$v=-10cm$

As v = -10 the image will be virtual and form in front of the lens.