In the sketch to the right, a long straight wire is in the plane of a rectangula
ID: 1432348 • Letter: I
Question
In the sketch to the right, a long straight wire is in the plane of a rectangular conducting wire loop. The current in the straight wire is up. At some point the current in the straight wire starts to increase in magnitude. This increased current leads to an induced current in the wire loop. In which direction will the induced current in the wire loop be? Explain how you reached this conclusion. How would your answer be different if the wire loop was on the left side of the wire instead of the right side?Explanation / Answer
Magnetic field due to straight wire is into the screen in the conducting wire loop. As current starts to increase, magnetic flux into the screen begins to increase. As per Lenz's law, induced current in loop will try to nullify this increase. Therefore current induced will be in counterclockwise direction to setup a magnetic field out of the screen in the loop.
b) If loop was on left side, then magnetic field direction in the loop will be reversed and induced current will be in clockwise direction.