Current Attempt in Progress High-voltage power lines are a familiar sight throughout the country. The aluminum (resistivity = 2.82 x 10-80 m) wire used for some of these lines has a cross-sectional area of 7.3 x 104 m². What is the resistance of 9.4 kilometers of this wire? Number i Units

a. Explain what is meant by the resistance of a resistor b. Explain why the resistance of a metal increases when its temperature increases  c. State 2 other factors which determine the resistance of a stated length of wire

Part A Variations in the resistivity of blood can give valuable clues about changes in various properties of the blood. Suppose a medical device attaches two electrodes into a 2.0-mm-diameter vein at positions 5.1 cm apart. What is the blood resistivity if a 9.0 V potential difference causes a 210 µA current through the blood in the vein? HA ? p = Value Units Submit Request Answer

19 q10 Car batteries are often rated in amp-hours. This rating indicates the quantity of charge that can pass through the battery before the battery's chemical energy must be restored by the car's generator or some other source. The amp-hour unit is convenient for simple calculations. For example, a 60-amp-hour battery can supply a current of 1.0 A for 60 h (or 60 A for 1.0 h) before going dead. Find the energy stored in the following. (a) a 56 A-h, 14 V car battery(b) a 1.1 A-h, 1.7 V flashlight battery

QUESTION 1 A lamp has a current of 1.95 A. In hours, how long does it take for 1 mole of electrons to pass through the lamp?

Real materials only have so many electrons (with fixed charge) that are free to move through a circuit. How can the same object allow different amounts of current to flow through it? Use what you noticed about the electrons in the simulation to justify your answer. image of simulation below

QUESTION 4 A physics student wishes to measure the voltage change and current across a resistor in a circuit using a voltmeter and an ammeter respectively. How should the student connect the voltmeter and ammeter to the circuit? a. The voltmeter should be connected in series with the resistor, and the ammeter should be connected in series with the resistor. O b. The voltmeter should be connected in series with the resistor, and the ammeter should be connected in parallel with the resistor. C. The voltmeter and ammeter should be connected in a series combination that is, in turn, connected in parallel with the resistor d. The voltmeter should be connected in parallel with the resistor, and the ammeter should be connected in parallel with the resistor. e. The voltmeter should be connected in parallel with the resistor, and the ammeter should be connected in series with the resistor.