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- An aluminum wire 1.628 mm in diameter (14-gauge) carries a current of 3.00 amps, (a) What is the absolute value of the charge density in the wire? (b) What is the drift velocity of the electrons? (c) What would be the drift velocity if the same gauge copper were used instead of aluminum? The density of copper is 8.96 g/cm3 and thedensity of aluminum is 2.70 g/cm3. The molar mass ofaluminum is 26.98 g/mol and the molar mass of copper is 63.5 g/mol. Assume each atom of metal contributes one free electron.arrow_forwardA 0.900-V potential difference is maintained across a 1.50-m length of tungsten wire that has a cross-sectional area of 0.600 mm2. What is the current in the wire?arrow_forwardAn isolated conducting sphere has a 10 cm radius. One wire carries a current of 1.000 002 0 A into it. Another wire carries a current of 1.000 000 0 A out of it. How long would it take for the sphere to increase in potential by 1000 V?arrow_forward
- 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 1.7-mm-diameter vein at positions 5.4 cm apart. What is the blood resistivity if a 9.0 V potential difference causes a 200 μA current through the blood in the vein?arrow_forwardA wire is 100.0 m long and 0.800 mm in diameter. The first x meters of the wire is made of copper and the rest of the wire is made of tungsten. When a 10.0 V potential difference is applied across the ends of the wire in a 20.0°C environment, a current of 1.16 A is observed. a) How much of the wire is made of copper? x = ______________________________ b) If the apparatus is moved to a 0.0°C environment, would you expect the current to increase, decrease, or remain constant? Explain your answer, including a description of what is going on inside the wire at a microscopic level. c) If the apparatus is moved to a 125°C environment, how much power will be dissipated by the wire? Explain what that means (what forms of energy are involved, what is the rate of energy transformation) P = ______________________________arrow_forwardIf you touch the two terminals of a power supply with your two fingertips on opposite hands, the potential difference will produce a current through your torso. The maximum safe current is approximately 5 mA.a. If your hands are completely dry, the resistance of your body from fingertip to fingertip is approximately 500 kΩ. If you accidentally touch both terminals of your 120 V household electricity supply with dry fingers, will you receive a dangerous shock?b. If your hands are moist, your resistance drops to approximately 1 kΩ. If you accidentally touch both terminals of your 120 V household supply with moist fingers, will you receive a dangerous shock?arrow_forward
- Variations in the resistivity of blood can give valuable clues to changes in the blood viscosity and other properties. The resistivity is measured by applying a small potential difference and measuring the current. Suppose a medical device attaches electrodes into a 1.5-mm -diameter vein at two points 5.0 cm apart. What is the blood resistivity of a 8.9 V potential difference causes a 240 μA current through the blood in the vein?arrow_forwardThe resistance of the body varies from approximately 500 kΩkΩ (when it is very dry) to about 1.0 kΩkΩ (when it is wet). The maximum safe current is about 5.3 mAmA. At 10 mAmA or above, muscle contractions can occur that may be fatal. What is the largest potential difference that a person can safely touch if his body is wet?arrow_forwardA copper wire is r = 2.19 cm in radius and 2.6 m in length, has a resistivity of 1.72x10^-8 Ω m, and carries a current of 3.23 A. The wire has a charge carrier density of 8.49x10^28 electrons/m3. What is the electric potential difference, V in volts, across the wire? Note: Express your answer to three significant figures. Use scientific notationarrow_forward
- A current-carrying gold wire has a diameter of 0.94 mm. The electric field in the wire is 0.52 V/m. What is (a) the potential between two points in the wire 6.8-m apart, (b) the resistance of a 6.8-m length of this wire, and (c) the current carried by the wire. Assume the gold’s resistivity value to be 2.4 x 10 - 8 Ω-m.arrow_forwardYou are working with an oceanographer who is studying how the ion concentration in seawater depends on depth. She shows you the device that she uses to measure the resistivity of water from a boat. It consists of a pair of concentric metallic cylinders at the end of a cable (as shown). Seawater flows freely between the two cylindrical shells. She makes a measurement by lowering the device into the water and applying a potential difference ΔV between the inner and outer cylinders. This produces an outward radial current I in the seawater between the shells. She shows you the current and voltage data for the water at a particular depth and is then called away to answer a long call on her cellphone about a laboratory issue back on the mainland. As she leaves, she says, “Have the resistivity of the water calculated when I get back.” She forgot to show you any tables or formulas to use to determine the resistivity, so you are on your own. Quick! Find an expression for the resistivity in…arrow_forwardA strip of doped silicon 260.0 um wide contains 8.80 x 10-2 conduction electrons per cubic meter and an insignificant number of holes. When the strip carries a current of 102 µA, the drift speed of the electrons is 59.6 cm/s. What is the thickness of the strip? Umarrow_forward
- Principles of Physics: A Calculus-Based TextPhysicsISBN:9781133104261Author:Raymond A. Serway, John W. JewettPublisher:Cengage LearningPhysics for Scientists and Engineers with Modern ...PhysicsISBN:9781337553292Author:Raymond A. Serway, John W. JewettPublisher:Cengage Learning