What is the position of the image when an object is placed at a distance of 20 cm from a concave mirror of focal length 20 cm ?

Open in App

Solution

Object distance, u = -20 cm
Focal length, f = -20 cm (concave mirror) Image distance, v =?

We know that,
$1 over v plus 1 over u equals 1 over f fraction numerator begin display style 1 end style over denominator begin display style v end style end fraction plus fraction numerator begin display style 1 end style over denominator begin display style left parenthesis negative 20 right parenthesis end style end fraction equals fraction numerator begin display style 1 end style over denominator begin display style left parenthesis negative 20 right parenthesis end style end fraction 1 over v equals 0 v space equals space infinity space left parenthesis i n f i n i t y right parenthesis$
So image is at infinity.

Suggest Corrections

129

Similar questions

Q. What is the position of the image when an object is placed at a distance of 20 cm from a concave mirror of focal length 20 cm?

At what distance from a concave mirror of focal length 10 cm should an object be placed so that : (a) its real image is formed 20 cm from the mirror ? (b) its virtual image is formed 20 cm from the mirror ?

An object is placed at a distance of 20 cm in front of a concave lens of focal length 20 cm. Find :

(a) the position of image, and

(b) the magnification of image.

6. a.An object 4 cm in size is placed at a distance of 25 cm from a concave mirror of focal
length 15 cm. Find the position, nature and height of the image.
b A converging mirror forms a real image of height 4 cm, of an object of height 1 cm
placed 20 cm away from the mirror. Calculate the image distance. What is the focal
length of the mirror?

Q. An object is placed at a distance of

10 c m

from the concave mirror and the image is formed

20 c m

in front of the mirror. The focal length of the mirror is:

Join BYJU'S Learning Program

What is the position of the image when an object is placed at a distance of 20 cm from a concave mirror of focal length 20 cm ?

Object distance, u = -20 cm Focal length, f = -20 cm (concave mirror) Image distance, v =? We know that, So image is at infinity.