By mirror formula,v1=u−fuf=−40+15(−40)(−15)=−25600=−24cm
When object is displaced by 20 cm towards mirror v2=u−fuf=−20+15(−20)(−15)=−60cm
Displacement of image =v2−v1=−36cm
= 36 cm away from the mirror
An object is placed at a distance of 40 cm from a concave mirror of focal length 15 cm. If the object is displaced through a distance of 20 cm towards the mirror, the displacement of the image will be
Held on 30 Apr 2018 · Verified 9 Jul 2026.
30 cm towards the mirror
36 cm away from the mirror
30 cm away from the mirror
36 cm towards the mirror
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