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Question
Using an electromagnet, you can make a working model of a railway signal as shown in figure.

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Solution

Working Model of a Railway Signal Using an Electromagnet
Components:
- Cardboard Signal: Indicates the railway signal.
- Electromagnet: Coil wrapped around an iron nail.
- Battery: Powers the electromagnet.
- Switch: Controls the electromagnet.
- Thread: Connects the electromagnet to the cardboard signal.
Steps:
-
Setup:
- Mount the cardboard signal on a stand.
- Attach a thread to the signal and pass it over a pulley to the electromagnet.
-
Electromagnet Creation:
- Wrap a coil of wire around an iron nail.
- Connect the coil to a battery via a switch.
-
Operation:
- Turning on the switch powers the electromagnet.
- The electromagnet pulls the iron nail, moving the thread and changing the signal's position.
- Turning off the switch deactivates the electromagnet, allowing the signal to return.
Visual Representation:
The provided image illustrates the setup with labelled components, demonstrating how the electromagnet controls the railway signal.
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An electric bell has an electromagnet.
If the direction of electric current in a solenoid when viewed from a particular end is anticlockwise, then this end of solenoid will be:
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The magnetic effect of current was discovered by:
(a) Maxwell
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When the switch S is closed in the figure given below, the pointer of the galvanometer moves to the right.
If S is kept closed, will the pointer:
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A student was asked to perform an experiment to study the force on a current carrying conductor in a magnetic field. He took a small aluminium rod AB, a strong horse shoe magnet, some connecting wires, a battery and a switch and connected them as shown. He observed that on passing current, the rod gets displaced. On reversing the direction of current, the direction of displacement also gets reversed. On the basis of your understanding of this phenomenon, answer the following questions:

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-
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OR
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