1. The magnetic flux that passes through one turn of a 15-turn coil of wire changes to 4.39 from 9.69 Wb in a time of 0.0677 s. The average induced current in the coil is 270 A. What is the resistance of the wire?

2. A constant magnetic field passes through a single rectangular loop whose dimensions are 0.44 m x 0.55 m. The magnetic field has a magnitude of 3.1 T and is inclined at an angle of 75^o with respect to the normal to the plane of the loop. (a) If the magnetic field decreases to zero in a time of 0.50 s, what is the magnitude of the average emf induced in the loop? (b) If the magnetic field remains constant at its initial value of 3.1 T, what is the magnitude of the rate A/ t at which the area should change so that the average emf has the same magnitude?

a.

b.

3. In astronomy, distances are often expressed in light-years. One light-year is the distance traveled by light in one year. If the distance to a star is 5.5 light-years, what is this distance in meters? (There are 365.25 days in one year.)