The current in a 100 watt lightbulb is 0.790 A. The filament inside the bulb is 0.260 mm in diameter. You may want to review (Pages 750-752). Part A What is the current density in the filament? Express your answer to three significant figures and include the appropriate units. Value Submit HÅ Part B Units Request Answer ? What is the electron current in the filament? Express your answer using three significant figures.

The current in a 100 watt lightbulb is 0.790 A. The filament inside the bulb is 0.260 mm in diameter. You may want to review (Pages 750-752). Part A What is the current density in the filament? Express your answer to three significant figures and include the appropriate units. Value Submit HÅ Part B Units Request Answer ? What is the electron current in the filament? Express your answer using three significant figures.

Physics for Scientists and Engineers: Foundations and Connections

1st Edition

ISBN:9781133939146

Author:Katz, Debora M.

Publisher:Katz, Debora M.

Chapter28: Current And Resistance

Section: Chapter Questions

Problem 69PQ

See similar textbooks

Similar questions

The vector current density of a 3-meter-long and 3mm diameter conductor is given as 155630 A/m2. Determine the current on the conductor, its free electron density, the drift velocity of the charges and the number of electrons passing through the conductor for 3 seconds.
The figure below represents a section of a circular conductor of nonuniform diameter carrying a current of I = 5.30 A. The radius of cross-section A1 is r1 = 0.510 cm. What is the magnitude (A/m2) of the current density across A1? Since the radius r2 at A2 is larger than the radius r1 at A1. will the current and current density at A2 larger, smaller, or the same? Assume A2 = 5A1. What is the radius, the current, and the current density at A2?
What is the current through a cylindrical wire of radius R = 0.1 mm if the current density is J = J0 R r , where J0 = 32000 A m2 ?
A general relationship for the current density carried by electrons of density /I is J = qnv. where q is the electronic charge and II is the electron velocity.
The magnitude of the current density in a certain lab with a circular cross section of radius R=4.00 mm is given by J= (3.00 × 10^8) r^2, with J in amperes per square meter and radial distance r in meters. What is the current through the outer section bounded by r = 0.500R and r = R ?
A wire has a current density of 6.01×106 A/m2. If the cross-sectional area of the wire is 2.91 mm2, what current ? does the wire carry? ?= A With this current, how much time ? is required for 4.15×1020 electrons to pass any point on the wire? ?=
A copper wire of 3mm diameter with conductivity of 6.7 * 10' (Q.m) , and electron mobility of 0.0064 m2 N sec. Is subjected to an electric field of 30 mV/m. Find (a) the charge density of free electrons, (b) the current density, (c) current flowing in the wire, (d) the electron draft velocity.
The quantity of charge Q that has passed through a surface of area 6.00 mm2 varies with time according to the equation Q = 2t2 + 10, where t is in seconds. What is the instantaneous current through the surface at t = 2.6 s?
A constant current transfers 10*10^14 electrons onto one plate of a capacitor in 3 minutes [min]. (a) What is the current, in units of amperes [A]? Express the answer using an appropriate SI prefix such that there are only 1, 2, or 3 digits shown to the left of the decimal. (b) If the capacitor has a capacitance of microfarads [F], what is the voltage in units of volts [V] across the capacitor?
A conductor carries a current that is decreasing exponentially with time. The current is modeled as I=I0et/ , where I0= 3.00 A is the current at timet = 0.00 s and =0.50 s is the time constant. How much charge flows through the conductor between t = 0.00 s and =3 ?
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.
A long coaxial cable, crossection of which is shown in the figure, is made up of a cylindrical inner wire of radius a and a cylindrical shell shaped coaxial outer wire of inner radius b and outer radius c. The current density with magnitude J = Kr2/a is spread over the cross section of the inner wire where the current has out-of-page direction. Outer wire carries uniformly distributed current i = πKa 3 having into-the-page direction. a) Find the total current of the inner wire iin in terms of ?.Find expressions for the magnitude of magnetic field, b) inside the inner wire (r < a) c) between the wires (a< r< b) d) inside the outer wire (b< r < c) e) outside the outer wire (r> c) in terms of i, π, μ and r. For each case indicate the direction of the magnetic field as well.