Concept explainers
(a)
The magnitude and direction of the electric field in the wire.
(a)
Answer to Problem 47PQ
The magnitude and direction of the electric field in the wire are
Explanation of Solution
Write the relation for the electric field in the wire.
Here,
Conclusion:
Substitute
Therefore, the magnitude and direction of the electric field in the wire are
(b)
The resistance of the wire.
(b)
Answer to Problem 47PQ
The resistance of the wire is
Explanation of Solution
Write the relation for the resistance of the cylindrical silver wire.
Here,
Conclusion:
Substitute
The resistance of the cylindrical silver wire is
(c)
The magnitude and direction of the current in the wire.
(c)
Answer to Problem 47PQ
The magnitude and direction of the current in the wire are
Explanation of Solution
Write the relation for the current in the cylindrical silver wire.
Here,
Conclusion:
Substitute
The current is in positive sign represents that it flows from left to right.
The magnitude and direction of the current in the wire are
(d)
The current density in the wire.
(d)
Answer to Problem 47PQ
The current density in the wire is
Explanation of Solution
Write the relation for the current density in the wire.
Here,
Conclusion:
Substitute
Therefore, the current density in the wire is
Want to see more full solutions like this?
Chapter 28 Solutions
EBK WEBASSIGN FOR KATZ'S PHYSICS FOR SC
- Unreasonable Results (a) What current is needed to transmit 1.00 102 MW of power at 10.0kV? (b) Find the resistance of 1.00 km of wire that would cause a 0.0100% power loss. (c) What is the diameter of a 1.00-km-long copper wire having this resistance? (d) What is unreasonable about these results? (e) Which assumptions are unreasonable, or which premises are inconsistent?arrow_forwardFour resistors are connected to a battery as shown in Figure P27.15. (a) Determine the potential difference across each resistor in terms of . (b) Determine the current in each resistor in terms of I. (c) What If? If R3 is increased, explain what happens to the current in each of the resistors. (d) In the limit that R3 , what are the new values of the current in each resistor in terms of I, the original current in the battery? Figure P27.15arrow_forwardTaking R = 1.00 k and = 250 V in Figure P27.19, determine the direction and magnitude of the current in the horizontal wire between a and e. Figure P27.19arrow_forward
- A student uses a 100.00-W, 115.00-V radiant heater to heat the student’s dorm room, dining the hours between sunset and sunrise, 6:00 p.m. to 7:00 a m. (a) What current does the heater operate at? (b) How many electrons move through the heater? (c) What is the resistance of the heater? (d) How much heat was added to the dorm room?arrow_forwardThe resistance between terminals a and b in Figure P27.36 is 75.0 . If the resistors labeled R have the same value, determine R. Figure P27.36arrow_forwardA particle accelerator produces a beam with a radius of 1.25 mm with a current of 2.00 mA. Each proton has a kinetic energy of 10.00 MeV. (a) What is the velocity of the protons? (b) What is the number (n) of protons per unit volume? (b) How many electrons pass a cross sectional area each second?arrow_forward
- 1. Silver is composed of 5.8 x 1028 free electrons per cubic meter. If a silver wire with a diameter of 1.8 mm can allow charges of 360 C to flow in 1 hour,a. What is the current in the conducting wire?b. What is the magnitude of the drift velocity of the electrons in the conducting wire?arrow_forwardA conducting rod with a circular cross-section (this rod is a cylinder) has a radius of 1o mm and is 2 metres long. The rod is made of aluminum, so its conductivity is 3.6 x 10' s/m. A potential difference (voltage) is applied at both ends of this rod and the current is I= 90 A. That's a lot of current! a. What is the resistance of the rod, when measured from one end to the other? b. Calculate the current density in the rod along its length. . Determine the electric field amplitude at all locations within the rod. d. What is the electric potential difference between the two ends of the rod.arrow_forwardAs part of a class project you are given 0.900 g of nichrome and asked to fabricate a wire with uniform cross-section. You use up 95% of the nichrome and make a wire with a resistance of 0.793 Ω. The resistivity of nichrome is 1.00 10-6 Ω · m and its density is 8.31 103 kg/m3. a. What length of wire do you end up with? b. What is the diameter of the wire?arrow_forward
- A 15 Ω resistor is connected to the terminals of a 1.5 V battery.a. Draw a graph showing the potential as a function of distance traveled through the circuit, starting from V = 0 V at the negative terminal of the battery.b. What is the current in the circuit?arrow_forwardAn uncharged capacitor with C=43μF and a resistor with R=75Ω are connected in series with a battery of ϵ=7.5 V. a. Express the time constant τ in terms of R and C. b. Calculate the numerical value of τ in microseconds. c. Express the maximum charge Q on the capacitor in terms of C and ϵ. d. Calculate the numerical value of Q in microcoulombs.arrow_forwardThe average resistivity of the human body (apart from sur face resistance of the skin) is about 5.0 Ω • m. The conducting path between the right and left hands can be approximated as a cylinder 1.6 m long and 0.10 m in diameter. The skin resistance can be made negligible by soaking the hands in salt water.a. What is the resistance between the hands if the skin resistance is negligible?b. If skin resistance is negligible, what potential difference between the hands is needed for a lethal shock current of 100 mA? Your result shows that even small potential differences can produce dangerous currents when skin is damp.arrow_forward
- Physics for Scientists and Engineers: Foundations...PhysicsISBN:9781133939146Author:Katz, Debora M.Publisher:Cengage LearningCollege PhysicsPhysicsISBN:9781305952300Author:Raymond A. Serway, Chris VuillePublisher:Cengage LearningCollege PhysicsPhysicsISBN:9781285737027Author:Raymond A. Serway, Chris VuillePublisher:Cengage Learning
- College PhysicsPhysicsISBN:9781938168000Author:Paul Peter Urone, Roger HinrichsPublisher:OpenStax CollegePhysics for Scientists and EngineersPhysicsISBN:9781337553278Author:Raymond A. Serway, John W. JewettPublisher:Cengage Learning