Electricity | Activities in Text Book with Solution
Activity 12.2
Take a nichrome wire, a torch bulb, a 10 W bulb and an ammeter (0 – 5 A range), a plug key and some connecting wires.
Set up the circuit by connecting four dry cells of 1.5 V each in series with the ammeter leaving a gap XY in the circuit, as shown in Fig. 12.4.
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| Fig. 12.4 |
Complete the circuit by connecting the nichrome wire in the gap XY. Plug the key. Note down the ammeter reading. Take out the key from the plug. [Note: Always take out the key from the plug after measuring the current through the circuit.]
Replace the nichrome wire with the torch bulb in the circuit and find the current through it by measuring the reading of the ammeter.
Now repeat the above step with the 10 W bulb in the gap XY.
Are the ammeter readings different for different components connected in the gap XY?
What do the above observations indicate?
You may repeat this Activity by keeping any material component in the gap. Observe the ammeter readings in each case. Analyse the observations.
✅ Answer: The current is different for different components. In certain components, there is easy flow of electric current while the others resist the flow.
Within a conductor, electrons are
not completely free to move due to the attraction by atoms. So, resistance is increased
and motion of electrons is retarded.