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27. Resistors & DC Circuits

Microscopic View of Current

27. Resistors & DC Circuits

Microscopic View of Current

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Microscopic View of Current

Microscopic View of Current

Douglas Lawrence

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Anderson Video - Electron Drift Example

Anderson Video - Electron Drift Example

Drift Velocity Derivation - A Level Physics

Drift Velocity Derivation - A Level Physics

Current from drift velocity (I = neAvd) | Electricity | Physics | Khan Academy

Current from drift velocity (I = neAvd) | Electricity | Physics | Khan Academy

Khan Academy India - English

Drift velocity (concept & intuition) | Electricity | Physics | Khan Academy

Drift velocity (concept & intuition) | Electricity | Physics | Khan Academy

Khan Academy India - English

Practice this topic

Multiple Choice

Typical household wiring in the United States is 14-gauge copper wire. 14-gauge wire has a radius of

0.815 mm

. What is the electron drift speed if a

10 A

current is carried in a 14-gauge wire?

Multiple Choice

What is the current density in a wire with a radius of

0.815 mm

carrying a current of

5.0 A

Multiple Choice

What current does a

0.23 V / m

electric field create in an iron wire of

0.8 mm

Multiple Choice

What is the electron current in a gold wire with a radius of

1.5 mm

when the electron drift speed is

1.0 \times 10^{- 4} m / s

Textbook Question

Pure silicon at room temperature contains approximately 1.0 * 10^16 free electrons per cubic meter. (a) Referring to Table 25.1, calculate the mean free time t for silicon at room temperature. (b) Your answer in part (a) is much greater than the mean free time for copper given in Example 25.11. Why, then, does pure silicon have such a high resistivity compared to copper?

Textbook Question

The two wires in FIGURE P27.63 are made of the same material. What are (b) the electron drift speed in the 2.0-mm-diameter segment of the wire?

Textbook Question

The electron drift speed is 2.0 X 10⁻⁴ m/s in a metal with a mean time between collisions of 5.0 x 10⁻¹⁴ . What is the electric field strength?

Textbook Question

(II) A 0.65-mm-diameter copper wire carries a tiny current of 3.2 μA. Estimate

(a) the electron drift speed,

Textbook Question

(II) A 0.65-mm-diameter copper wire carries a tiny current of 3.2 μA. Estimate

(b) the current density, and

Textbook Question

(II) A 5.30-m length of 2.0-mm-diameter wire carries a 750-mA current when 22.0 mV is applied to its ends. If the drift speed is 1.7 x 10⁻⁵ m/s, determine

(b) the resistivity ρ,

Textbook Question

(II) At a point high in the Earth’s atmosphere, He²⁺ ions in a concentration of 2.8 x 10¹²/m³ are moving due north at a speed of 2.0 x 10⁶ m/s. Also, a 7.0 x 10¹¹ / m³ concentration of O⁻₂ ions is moving due south at a speed of 6.2 x 10⁶ m/s . Determine the magnitude and direction of the current density j→ at this point.

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