Question

1. A wire carrying a current of I = 0.845 ± 0.001A is brought in close proximity of a bar magnet resting on a scale, and the wire does not make contact with either the surface of the scale or the bar magnet. Provide a physical explanation of what is happening in the experiment. In your answer, make a connection to the method of electrostatically influencing scale readings studied. Explain the similarities and differences.

2) What is the magnitude of the magnetic field of the bar magnet? You can assume that the magnetic field is approximately uniform in the region of interest and that the bar magnet has a width of d = 3.0cm.

3) Now, consider the application of magnetic fields and forces. It has long been postulated that migrating birds navigate via an interaction between their axon currents and Earth's magnetic field. Axon currents are known to be on the order of I₀ = 10nA (that is, 10*10-9 Amps), and axon lengths vary greatly but are limited by the size of the animal. Make a reasonable assumption about the maximum axon length of a Canada goose, a common North American migratory bird. Record your assumed axon length (L_axon).

4)Using the axon length you indicated above, determine the magnitude of the maximum magnetic force, FB, a migrating Canada goose would feel from Earth's magnetic field.

Answer 1