Question

An object is placed at a distance of 30cm from a concave lens of focal length 15cm. Find position and nature of image​

Answer 1

Explanation:

List four characteristics (nature, position, etc.) ... object is placed at a distance of 30 cm from a concave lens of focal length ... Find the position and so it forms an image at 15 cm from the lens ?

Answer 2

As We know that Object is placed at a distance of 30 cm from the Concave lens of Focal length of 15 cm.

• Object (u) = –30 cm
• Focal length (f) = –15 cm

Let the Position of the Image be v.

By using the lens formula, we can calculate the image position by 1/v – 1/u = 1/f.

→ 1/v – 1/u = 1/f

→ 1/v + 1/30 = 1/-15

→ 1/v = 1/–15 - 1/30

→ 1/v = –2–1/30

→ 1/v = –3/30

→ 1/v = –1/10

→ v = –10 cm

Hence,

The Position of the image will be 10 cm to the left side of lens (at the side of object).

Nature of Image: This Formed image will be Virtual & Erect as well as smaller in size (with respect to the Object).