A carbon resistor is 4 mm long and has a constant cross section of 0.2 mm2. The conductivity of carbon at room temperature is 3 × 104 per ohm·m. In a circuit its potential at one end of the resistor is 12 volts relative to ground, and at the other end the potential is 16 volts. Calculate the resistance and the current .

Acommon technique in analysis of scientific data is normalization. the purpose of normalizing data is to eliminate irrelevant constants that can obscure the salient features of the data. the goal of this experiment is to test the hypothesis that the flux of light decreases as the square of the distance from the source. in this case, the absolute value of the voltage measured by the photometer is irrelevant; only the relative value conveys useful information. suppose that in part 2.2.2 of the experiment, students obtain a signal value of 162 mv at a distance of 4 cm and a value of 86 mv at a distance of 5.7 cm. normalize the students' data to the value obtained at 4 cm. (divide the signal value by 162.) then calculate the theoretically expected (normalized) value at 5.7 cm.