07 Electric Current - Electric Current Any electric charge...

Info iconThis preview shows pages 1–8. Sign up to view the full content.

View Full Document Right Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: Electric Current Any electric charge placed in electric field F experiences an electric force = q × F F q If there is a potential difference between two points, the electric field exists in the space between them Electric Field makes mobile charges moving F q If the charge is “free” or “mobile”, then in the electric field it would move (“drift”) pushed by the electric force. The charge drift velocity, v = μ × F, Here μ is a coefficient called “mobility” Electric Field causes Electric Current in conductors F q “Conductor” is any material that contains a lot of “free” or “mobile” charge. When a conductor is placed in an electric field, the mobile charges in it start moving (“drifting”). Moving mobile charges form an electric current Electric Current s Electric current is the rate of electric charge transfer. s Electric current is measured as the charged transferred through any cross- section of the conductor per unit time t Q I Δ Δ = Δ Q is the charge crossing the reference plane of a conductor per time Δ t q Electric Current Example 1 If each marble is charged and carries the electric charge 0.1 C and 10 marbles pass through the open end of the tube per 1 second, the current is ( ) 0 1 10 1 1 1 C Charge I C s A Time s × = = = = . / 1 1 A C s = / Current is measured in Amperes: Electric Current Example 2 Consider a nano-tube filled with a fluid. The fluid contains positively charged mobile molecules. There are 10 5 charged molecules per 1 cm of the nano-tube length. Each molecule has a charge of +1.6 × 10-19 C. In applied field, the molecules move with the drift velocity v = 10 3 cm/s....
View Full Document

Page1 / 27

07 Electric Current - Electric Current Any electric charge...

This preview shows document pages 1 - 8. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online