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Question
Observe the following diagram and choose the correct alternative:
Options
The intensity of magnetic field in A is larger than in B.
The intensity of magnetic field in B is less than in A.
The intensity of magnetic field A and B is same.
The intensity of magnetic field in A is less than in B.
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Solution
The intensity of magnetic field in A is less than in B.
Explanation:
Magnetic field produced due to closed loop
`vec"B" ⇒ vec"B" ∝ "I"`
In diagram (A), I = `5/("R"_1 + "R"_2)`
In diagram (B), I = `5/((("R"_1 "R"_2))/("R"_1 + "R"_2))`
IB > IA so `vec"B"_"B" > vec"B"_"A"`
∴ The intensity of magnetic field in A is less than in B.
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