Mean drift velocity

Describe the movement of charge carriers in metals

Free electrons often collide with positive ions whilst moving toward the positive terminal resulting in random movement

What is number density and what effect does it have?

Its the number of charge carriers pet m³ of a material

If its high, theres a greater number of charge carriers per m³ making it better at electric conductivity

If its low, theres a lower number of charge carriers per m³ making it worse at electric conductivity

Draw a chart showing materials in order of increasing number densities

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What is mean drift velocity?

Average velocity of a charged particle throughout conductors

What is the equation for current that includes cross sectional area, number density, elementary charge and mean drift velocity?

I = A x n x e x v

I = current, A

n = number density

e = elementary charge, 1.6×10^-19 C

v = mean drift velocity, ms^-1