Reflection

• Reflection happens when light bounces back after hitting a surface.
• Smooth, shiny surfaces like mirrors and still water give a clear, regular reflection.
• Rough surfaces, like a cloth or a wall, scatter light in many directions, giving no clear image.
• A plane mirror forms an image that is the same size as the object but is laterally inverted (left and right appear swapped).
• A periscope uses two plane mirrors placed at an angle to let us see over an obstacle, as used in submarines.

Level 1 - Core idea

Verbal: Reflection is the bouncing back of light from a surface. Smooth, shiny surfaces like plane mirrors give clear reflections, forming same-size images that are left-right reversed, while rough surfaces scatter light unevenly.

Symbolic: light hits smooth shiny surface -> regular reflection -> clear image; light hits rough surface -> scattered reflection -> no clear image

Visual: Look at yourself in a plane mirror and raise your right hand — your mirror image appears to raise its left hand, showing lateral inversion.

Level 2 - NCERT anchor

NCERT Looking Around 5 connects this to daily use of mirrors for grooming and the ambulance-word example written in reverse for rearview mirrors.

Why is the word on the front of an ambulance often written in a mirrored, reversed way?

Step 1 - Drivers ahead see the ambulance through their rearview mirror.
Step 2 - A plane mirror shows a laterally inverted (left-right reversed) image.
Step 3 - Writing the word reversed makes it read correctly in the mirror.
Answer: It is written reversed so it appears correct when seen in a rearview mirror.

Why can you see your reflection clearly in a mirror but not in a rough cloth?

Step 1 - A mirror is smooth and shiny.
Step 2 - Smooth surfaces reflect light in an organised, regular way.
Step 3 - A rough cloth scatters light in many directions instead.
Answer: The mirror gives a clear image because its smooth surface reflects light regularly.

• What is reflection of light?
• Which type of surface gives a clear, regular reflection?
• What does 'laterally inverted' mean for a mirror image?
• Why is the word on an ambulance often written reversed?
• Stretch: How do the two mirrors in a periscope work together to help you see over a wall?

Revision tip: Stand in front of a mirror and raise one hand to see lateral inversion for yourself.

Open the Practice tab for graded questions on Reflection.