Earth’s magnetic field The strength of Earth’s magnetic field varies with the depth below...

Earth’s magnetic field The strength of Earth’s magnetic field varies with the depth below the surface. The strength at depth z and time t can sometimes be approximated using the damped sine wave

where A0,α, and k are constants.

(a) What is the damping factor?

(b) Find the phase shift at depth z0.

(c) At what depth is the amplitude of the wave one-half the amplitude of the surface strength?