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ICE Princess25 [194]
3 years ago
11

A small but measurable current of 5.8 × 10-10 A exists in a copper wire whose diameter is 3.0 mm. The number of charge carriers

per unit volume is 8.49 × 1028 m-3. Assuming the current is uniform, calculate the (a) current density and (b) electron drift speed.

Physics
2 answers:
swat323 years ago
8 0

Answer:

a) The current density ,J = 2.05×10^-5

b) The drift velocity Vd= 1.51×10^-15

Explanation:

The equation for the current density and drift velocity is given by:

J = i/A = (ne)×Vd

Where i= current

A = Are

Vd = drift velocity

e = charge ,q= 1.602 ×10^-19C

n = volume

Given: i = 5.8×10^-10A

Raduis,r = 3mm= 3.0×10^-3m

n = 8.49×10^28m^3

a) Current density, J =( 5.8×10^-10)/[3.142(3.0×10^-3)^2]

J = (5.8×10^-10) /(2.83×10^-5)

J = 2.05 ×10^-5

b) Drift velocity, Vd = J/ (ne)

Vd = (2.05×10^-5)/ (8.49×10^28)(1.602×10^-19)

Vd = (2.05×10^-5)/(1.36 ×10^10)

Vd = 1.51× 10^-5

Soloha48 [4]3 years ago
5 0

Answer: a) J = 8.2×10^-5A/m^2

b) V = 6.07×10^-15m/s

Explanation:

The current density is the ratio of current to area of the wire.

J = i/A

Drift speed is inversly proportional to the square of the radius of the wire.v α 1/r^2

Please find the attached file for the solution

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            No;  the sample could not be aluminum;
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Density is expressed as "mass per unit volume" ;

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  The formula for density:  D = m/V ;

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Given:  A sample has a mass of 52.0 g ; and Volume of 17.1 cm³ ; could it be aluminum?
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Let us divide the mass of the sample by the volume of the sample;
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Atomic number is defined as the number of protons in the nucleus of an atom. IT is represented by Z.

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