Q. A neutron star has a mass of 2.0*10^30 kg (about the mass of our sun) and a radius of 5.2*10^3 m (about the height of a good-sized mountain). Suppose an object falls from rest near the surface of such a star. How fast would it be moving after it had fallen a distance of 0.012 m? (Assume that the gravitational force is constant over the distance of the fall, and that the star is not rotating.)
Q. A 10.80 cm diameter wire coil is initially oriented so that its plane is perpendicular to a magnetic field of 0.680 T pointing up. During the course of 0.160 s, the field is changed to one of 0.250 T pointing down. What is the average induced emf in the coil?