How much heat, in joules and in calories, must be added to a 75.0â–g iron block with a specific heat of 0.449 j/g â°c to increase its temperature from 25 â°c to its melting temperature of 1535 â°c?

Place several e-field sensors at a few points on different equipotential lines, and look at the relationship between the electric field and the equipotential lines. which statement is true? 1-at any point, the electric field is perpendicular to the equipotential line at that point, and it is directed toward lines of higher voltages. 2-at any point, the electric field is perpendicular to the equipotential line at that point, and it is directed toward lines of lower voltages. 3-at any point, the electric field is parallel to the equipotential line at that point.