1. A 115 V electric iron draws 5.57 A of current. How much heat is developed per hour?
2. At 39.2?C, the resistance of a segment of gold wire is 151.4 ?. When the wire is placed in a liquid bath, the resistance decreases to 96.9 ?. What is the temperature of the bath? The temperature coe?cient of resistivity for gold is 0.0034 (?C)?1 at 20?C.