Question 15 Marks
a. Define power of a lens and write its SI unit. Name the type of lens whose power is negative.
b. A convex lens forms a real and inverted image of finite size at a distance of 50 cm from it. Where is the object placed in front of the lens? Give all possible positions of the object stating reason in each case.
c. Draw labelled ray diagram for any one position of the object mentioned in (b) above.
b. A convex lens forms a real and inverted image of finite size at a distance of 50 cm from it. Where is the object placed in front of the lens? Give all possible positions of the object stating reason in each case.
c. Draw labelled ray diagram for any one position of the object mentioned in (b) above.
Answer
View full question & answer→a. Power of a lens is the Ability of a lens to diverge or converge light rays and SI unit of Power - diopter (D).Type of lens whose power is negative is Concave lens.
b. Position of object:
i. Beyond $2 F_{1}$
ii. At $2 \mathrm{~F}_{1}$
iii. Between $2 \mathrm{~F}_{1}$ and $\mathrm{F}_{1}$
c. Labelled ray diagram -
b. Position of object:
i. Beyond $2 F_{1}$
ii. At $2 \mathrm{~F}_{1}$
iii. Between $2 \mathrm{~F}_{1}$ and $\mathrm{F}_{1}$
c. Labelled ray diagram -
