NCERT Solutions Curiosity Chapter 3 Activity 3.1: Let us explore — A Torchlight
Book page 24 Updated on2026-09-05
Q1.
Take a torchlight similar to the one shown in Fig. 3.1. Observe it carefully. Do you notice a lamp? And a switch?
Answer
Yes — both are easy to find.
The lamp sits behind the glass or plastic window at the front of the torch, inside a shiny curved cup (the reflector) that throws the light forward. It may be a small incandescent bulb or one or more LEDs.
The switch is the small sliding button (or push button) on the side of the barrel, placed where your thumb naturally rests.
Check it yourself: Hold the torch and slide the switch without looking at the lamp. You can usually feel a small click — that click is the moment the metal strip inside touches and the circuit closes.
Q2.
Slide its switch and observe. Does the torch lamp glow? Now slide the switch back to its original position and observe the torch lamp.
Answer
Yes, in one position of the switch the lamp glows; when the switch is slid back, it goes off.
Switch slid one way → circuit closed → current flows → lamp glows (ON)
Switch slid back → circuit open → no current → lamp does not glow (OFF)
The position in which the lamp glows is called the ON position of the switch; the other position is the OFF position.
Q3.
Now, open the torchlight. What do you find inside?
Answer
Inside the barrel you find two or more electric cells, placed one behind the other, along with the parts that connect them.
A careful look shows all of these:
Electric cells — placed in a line, the + cap of one cell touching the – disc of the next.
A spring at the back end, which presses the cells firmly against the contacts.
Metal strips or wires running along the inside of the barrel to carry the current to the lamp.
The lamp and its reflector at the front, and the switch in between.
Why it happens: A torch is nothing more than a neat, packed-up electrical circuit — cells (the source), wires and metal strips (the path), a lamp (the device) and a switch (the control). Everything you will study in this chapter is already inside your hand.