1. The problem statement, all variables and given/known data A 1.88 m long wire carrying 3.1 A is wound into a tight, loop shaped coil 0.05 cm in diameter. What is the magnetic field at its center? 2. Relevant equations 3. The attempt at a solution I use Ampere's law but i get the wrong answer. I think i did not set up the equation right. Please i need answer with equation so i can compare it to mine not a chat. Thank you for your comprehension.