3.1 Activity: Observing Torchlight Components and Operation

What is a Torchlight?

It is a portable device that uses electric cells to make a lamp glow .

• Torchlight has three main parts we can see.

• Switch controls when the lamp glows or stops glowing.

• Inside torchlight we find two or more electric cells .

Activity 3.1: Observing a Torchlight (Page 24)

What you need:

• A torchlight similar to Fig. 3.1

What to do:

• Step 1: Take a torchlight and observe it carefully
• Step 2: Notice if there is a lamp and a switch
• Step 3: Slide the switch and observe if the torch lamp glows
• Step 4: Slide the switch back to original position and observe the torch lamp again
• Step 5: Open the torchlight and see what is inside

Embedded Questions:
Question: Do you notice a lamp?
Answer: Yes, it is present at the front end of the torchlight.

Question: And a switch?
Answer: Yes, it is present on the side of the torchlight.

Question: Does the torch lamp glow?
Answer: It glows only when the switch is in one position .

Observations

What you see:

• In the first position of switch, torch lamp glows
• In the other position , lamp does not glow
• Inside the torchlight, you find two or more electric cells

Why this happens:
We have studied that a switch either completes or breaks a circuit . This is why the lamp glows only in one position .

• Switch completes circuit - current flows - lamp glows
• Switch breaks circuit - no current flows - lamp stops

Question (Page 24): Why does the torch lamp glow in one position of its switch?

Answer:
We have studied that a switch is a device that completes or breaks a circuit . This is why it glows in one position only.

• One position - switch completes circuit - current flows
• Other position - switch breaks circuit - no current

Section Summary: A Torchlight