Find magnetic field at point ' 𝑂 ' in the given figure shown.
Correct Answer :
Solution :
The correct answer is:
Step-by-step Explanation:
From the given diagram, the system consists of two parts:
1. A circular current loop of radius R carrying a current I in the clockwise direction.
2. A long straight wire placed tangentially to the circular loop at a perpendicular distance R from center O, carrying current I towards the right.
1. Magnetic Field due to the Circular Loop (B1):
The magnitude of the magnetic field at the center O due to a circular current-carrying loop of radius R is given by:
Using the Right-Hand Thumb Rule, since the current flows clockwise around the center O, the direction of magnetic field B1 is directed into the page (⊗).
2. Magnetic Field due to the Straight Wire (B2):
The magnitude of the magnetic field at point O located at a distance R from an infinitely long straight wire carrying current I is given by:
Using the Right-Hand Palm Rule, since the current in the straight wire flows towards the right and point O lies above the wire, the magnetic field B2 is directed out of the page (⊙).
3. Net Magnetic Field at Point O (Bnet):
Since B1 (into the page) and B2 (out of the page) act in opposite directions, the net magnetic field magnitude at point O is:
Substituting the expressions for B1 and B2:
Factoring out :
Thus, the magnitude of the net magnetic field at point O is (directed into the page).
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