Q. 33 B5.0( 2 Votes )

# An object is kept

Answer :

(a) Given

Object distance (u) = -100cm

Focal length (f) = 50cm

Image distance = v

By lens formula;

⇒ v=100cm

Hence the image is formed at 100 cm behind the lens.

Object distance (u) = -100cm

Focal length (f) = -25cm

Image distance = v

By lens formula;

⇒ v =

⇒ v= -20cm

Hence the image is formed at 20cm in front of the lens.

(b) For 1st case

Object distance (u) = -100cm

Image distance (v) = 100cm.

By Magnification Formula

Magnification (m) =

⇒ Magnification =

Therefore, Magnification for the 1st case is -1. The negative sign means the image is real and inverted.

For 2nd case

Object distance (u) = -100cm

Image distance (v) = -20cm.

By Magnification Formula

Magnification (m) =

⇒ Magnification =

Therefore, Magnification for 2nd case is 0.2. The positive sign means the image is erect and virtual.

Rate this question :

If the image formXam idea - Science

The image of an oAll In One Science

List the sign conAll In One Science

An object is keptAll In One Science

A 2.0 cm tall objTogether With Science

A 5 cm tall objecTogether With Science

<span lang="EN-USNCERT - Science Exemplar

Name the physicalLakhmir Singh & Manjit Kaur - Physics

The magnificationXam idea - Science

How far should anAll In One Science