Physics-
General
Easy
Question
A length L of wire carries a steady current /. It is bent first to form a circular plane coil of one turn. The same length is now bent more sharply to give a double loop of smaller radius. The magnetic field at the centre caused by the same current is
- A quarter of its first value
- Unaltered
- Four times of its first value
- A half of its first value
The correct answer is: Four times of its first value
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