Question

1. At a super-sensitive gravitational wave detector, absolutely everything that could influence the instrument needs to be accounted for. Suppose one of the detectors was about 500 meters away from a high voltage power line which can carry up to 50 A of current. The detector is on the ground and the power lines are clearly strung high over head but the power lines are not directly above the detector. The distance (500 m) is directly from the wire to the detector. What is the magnitude of the magnetic field at the detector? Compare this to the size of the earth’s magnetic field (5×10-5T). Draw a diagram of the power lines and the detector (just one location) and indicate the direction of the magnetic field. The drawing must be self-consistent, but there are many, many ways of representing the situation. You will need to specify direction of the current in the wire and where the detector is in relation to the wire.

Answer 1