Login/Sign Up
Home » A concave lens of focal length 15 cm forms an image 10 cm from the lens. How far is the object placed from the lens? Draw the ray diagram.
A concave lens of focal length 15 cm forms an image 10 cm from the lens. How far is the object placed from the lens? Draw the ray diagram.
CBSE | Class 10 | Guides | Light Reflection and Refraction | NCERT Exemplar | Science
A concave lens of focal length 15 cm forms an image 10 cm from the lens. How far is the object placed from the lens? Draw the ray diagram.

Answer-

According to the question, focal length of concave lens (OF1) is f = – 15 cm

Image distance (v) is – 10 cm

Using the lens formula –

1/f = 1/v – 1/u

Or, 1/v = 1/f + 1/u = – 1/(10) – 1/(-15)

1/v = -5/150

v = – 30 cm

The object is 30 cm in front of the lens, as shown by the negative value of u. This is depicted in the ray diagram below.

i

More Material