Directions: In the following questions, a statement of assertion (A) ...
If the current is increased in the conductor the deflection of the compass needle increases. This is because the strength of the magnetic field varies directly as the magnitude of the electric current, or the current passing through the wire.
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Directions: In the following questions, a statement of assertion (A) ...
Assertion: A compass needle is placed near a current carrying wire. The deflection of the compass needle decreases when the compass needle is displaced away from the wire.
Reason: Strength of a magnetic field decreases as one moves away from a current carrying conductor.
Explanation:
When a current flows through a wire, it creates a magnetic field around the wire. This magnetic field can be detected using a compass needle. The needle of a compass is a small magnet that aligns itself with the Earth's magnetic field. When the compass needle is placed near a current carrying wire, the magnetic field created by the wire interacts with the Earth's magnetic field and causes the needle to deflect.
When the compass needle is displaced away from the wire, the magnetic field created by the wire becomes weaker. This is because the magnetic field strength decreases as one moves away from the current carrying conductor. The magnetic field follows an inverse square law, which means that the strength of the magnetic field decreases with the square of the distance from the wire.
As the magnetic field strength decreases, the interaction between the magnetic field of the wire and the Earth's magnetic field also decreases. This leads to a decrease in the deflection of the compass needle. When the compass needle is closer to the wire, the magnetic field is stronger, resulting in a larger deflection. However, as the distance between the compass needle and the wire increases, the magnetic field becomes weaker, leading to a decrease in the deflection of the compass needle.
Conclusion:
Both the assertion and the reason are true. The reason provides a correct explanation for the assertion. The deflection of the compass needle decreases when the compass needle is displaced away from the wire because the strength of the magnetic field decreases as one moves away from a current carrying conductor.
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