Question

The image formed by a thin lens is shown in the figure.

1. What is the nature of the image 

2. Find out the power of the image 

3. Draw the ray diagram showing above lens forming a magnified erect, virtual image 

4. If a convex lens of focal length 20 cm is kept in contact with above lens. What is the focal length and power of the combination

Answer 1

1. Inverted.

2. P = \(\frac{1}{1}\) = ID

3. 

4. P = P₁ + P₂

in this case f₁ = 1 m, f₂ = 0.2 m

P = \(\frac{1}{f_1}+\frac{1}{f_2}=\frac{1}{1}+\frac{1}{0.2}\) = 6D