NCERT Solutions for Class 7th Science Chapter 11 .6 Images Formed in a Plane Mirror — Activity 11.8: Let us experiment
Book page 161 & 16211 Updated on2026-09-19
Q1.
Now, stand close to the mirror. Is the image also closer to the mirror?
Fig. 11.11, page 161 (redrawn sketch): a student standing in front of a plane mirror, looking at his own image in it.
Answer
Yes. When you stand close to the mirror, your image also appears close to the mirror — just behind it. Step back, and the image goes back by the same amount.
Try This: Walk slowly towards a mirror. Your image walks towards you at the same speed, so the gap between you and your image closes twice as fast as your own steps.
Q2.
Stand at different distances from the mirror and notice how far the image appears to be from the mirror in each case. Do you find any relation between your distance from the mirror and the distance of your image from the mirror?
Fig. 11.11, page 161 (redrawn sketch): a student standing in front of a plane mirror, looking at his own image in it.
Answer
Yes — a very simple one:
distance of the image behind the mirror = distance of the object in front of the mirror
If you stand 1 m in front of the mirror, your image is 1 m behind it, and it looks 2 m away from you. Stand 3 m away and the image is 3 m behind the mirror.
The image in a plane mirror is always as far behind the mirror as the object is in front of it, and it is of the same size.
Q3.
Raise your left arm. Which arm does your image raise? Touch your right ear. Which ear does your image touch?
Answer
Raise your left arm and the image raises what looks like its right arm. Touch your right ear and the image touches what looks like its left ear.
This left–right swap in a mirror image is called lateral inversion. There is lateral inversion in the images formed by a plane mirror.
Why it happens: The mirror does not really turn you round; it simply sends back each point of you straight across the mirror. The point nearest your left side comes back on the side we call the image's right. So sides are exchanged, while top and bottom are not — the image stays erect.
Did you know? This is why AMBULANCE is painted reversed on the front of the van. A driver ahead sees it in the rear-view mirror, where lateral inversion turns it back into ‘AMBULANCE’, easy to read at a glance.