A ray of light passes from air into water. For its

PHY 184 Week 9 Notes-Magnetic Fields & Electromagnetic Induction 10/24-10/27  Moving charges produce a magnetic field o The Biot-Savart Law establishes this relation  Wires produce a magnetic field o Can be seen by a compass near the wires μ d B= 0 ids×^ ⏞= ⃗ o 4π r2 ; r  μ0 is the magnetic permeability of free space  4π 10 -7  To calculate B at P just integrate along the path  Solving for B using symmetry gives B= μ0i o 2πd 2 Parallel Wires  Consider a wire with current i a d1stance d away, with another wire nearby with current i .2 o They will attract  Magnetic Force is given by F=i2L B1si