Q1. A circular coil enclosing an area of 97 cm2 is made of 197 turns of copper wire. The wire making up the coil has resistance of 6.0, and ends of the wire are connected to form a closed circuit. Originally, a 1.3 T uniform magnetic field points perpendicularly upward through the plane of the coil. The direction of the field then reverses so that the final magnetic field has a magnitude of 1.3 T and points downward during the coil. If the time required for the field to reverse directions is 0.16 s, what average current flows during the coil during that time?
Q2. After a tornado, a 0.55-g straw was found embedded 2.8 cm into the trunk of a tree. If the average force exerted on the straw by the tree was 70 N, what was speed of the straw when it hit the tree?