Showing 1 to 10 of 333 Questions
  • (a) A 115-g mass of aluminum is formed into a right circular cylinder, shaped so that its diameter equals its height. Calculate the resistance between the top and bottom faces of the cylinder at 20°C. (b) Calculate the resistance between opposite faces if the same mass of aluminum is formed into a cube.

    0
    272
  • (a) A 34.5-m length of copper wire at 20.0°C has a radius of 0.25 mm. If a potential difference of 9.0 V is applied across the length of the wire, determine the current in the wire. (b) If the wire is heated to 30.0°C while the 9.0-V potential difference is maintained, what is the resulting current in the wire?

    0
    516
  • (a) A sheet of copper (ρ = 1.7 × 10–8 Ω ∙ m) is 2.0 mm thick and has surface dimensions of 8.0 cm × 24 cm. If the long edges are joined to form a tube 24 cm in length, what is the resistance between the ends? (b) What mass of copper is required to manufacture a 1 500-m-long spool of copper cable with a total resistance of 4.5

    0
    252
  • (a) At room temperature what is the strength of the electric field in a 12-gauge copper wire (diameter 2.05 mm) that is needed to cause a 2.75-A current to flow? (b) What field would be needed if the wire were made of silver instead?

    1
    1597
  • (a) At what temperature would the resistance of a copper conductor be double its resistance at 20.0°C? (Use 20.0°C as the reference point in Eq.26-17; compare your answer with Figure)(b) Does this same "doubling temperature" hold for all copper conductors, regardless of shape or size?

    0
    480
  • (a) Determine the resistance of a lightbulb marked 100 W @ 120 V. (b) Assuming that the filament is tungsten and has a cross-sectional area of 0.010 mm2, determine the length of the wire inside the bulb when the bulb is operating. (c) Why do you think the wire inside the bulb is tightly coiled? (d) If the temperature of the tungsten wire

    0
    338
  • (a) Make an order-of-magnitude estimate of the resistance between the ends of a rubber band. (b) Make an order-of-magnitude estimate of the resistance between the ‘heads’ and ‘tails’ sides of a penny. In each case state what quantities you take as data and the values you measure or estimate for them. (c) WARNING! Do not try th

    0
    356
  • (a) What is the potential difference Vad in the circuit of Fig? (b) What is the terminal voltage of the 4.00-V battery? (c) A battery with emf 10.30z V and internal resistance 0.50 0 is inserted in the circuit at d, with its negative terminal connected to the negative terminal of the 8.00-V battery. What is the difference of potential Vbc

    3
    953
  • (a) What is the resistance between the hands if the skin resistance is negligible? (b) What potential difference between the hands is needed for a lethal shock current of 100 mA? (Note that your result shows that small potential differences produce dangerous currents when the skin is damp.) (c) With the current in part (b), what power is

    0
    850
  • (a) What is the resistance of a Nichrome wire at 0.0°C if its resistance is 100.00 0 at 11.5°C?(b) What is the resistance of a carbon rod at 25.8°C if its resistance is 0.0160 0 at 0.0°C?

    0
    608
Suggested Freelancers
    Loading Freelancers