NCERT Solutions for Class 7th Social Science Chapter 19 After Rani’s voice note travels from Madhya Pradesh to Tamil Nadu — THINK ABOUT IT
Book page 185 Updated on2026-09-19
Q1.
Which parts of this process do you think are easiest to see in real life, and which are completely invisible?
Answer
Only the two ends and the tower are easy to see; almost everything in the middle is hidden. Sort the journey the chapter describes into what your eyes can reach and what they cannot.
Stage of Rani’s voice note
Can you see it?
Why
The two phones — tap, record, send
Easily seen
They are in our hands every day
Electricity powering the mobile tower
Partly seen
You can see the tower and the power lines going to it, but not the current flowing
The mobile tower near her village
Easily seen
Tall lattice masts stand above rooftops and fields
Fibre cables buried under fields and roads
Invisible
Underground; you notice them only when a road is dug up and a warning marker appears
Transmission to satellites in space
Invisible
Both the signal and the satellite are far beyond sight
Giant servers in distant cities
Invisible
Data centres are ordinary-looking buildings, usually far from where we live
The message arriving on the cousin’s phone
Easily seen
The visible end of the whole chain
Solid boxes are the parts of the journey we can actually see; dashed boxes are the invisible parts that do most of the work.
Why it happens: the visible parts are the ones that must be near people — a phone in a hand, a tower where the users are. The invisible parts are hidden on purpose: cables are buried so that traffic and weather do not damage them, satellites must be in space to cover a whole country at once, and servers are kept in guarded, cooled buildings. So the rule is simple — the closer a piece of infrastructure is to the user, the more visible it is.
Tip: This is also why people notice a pothole at once but never notice a fibre cable. Damage to the invisible parts is discovered only when the service stops.