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A wire with a length of 150 m and a radius of 0.15 mm carries a current with a uniform current density of 2.8 x 10^7A/m^2. The current is: A) 2.0 A B) 0.63 A C) 5.9A D) 300 A E) 26000 A

Respuesta :

Answer:

The current is 2.0 A.

(A) is correct option.

Explanation:

Given that,

Length = 150 m

Radius = 0.15 mm

Current density[tex]J=2.8\times10^{7}\ A/m^2[/tex]

We need to calculate the current

Using formula of current density

[tex]J = \dfrac{I}{A}[/tex]

[tex]I=J\timesA[/tex]

Where, J = current density

A = area

I = current

Put the value into the formula

[tex]I=2.8\times10^{7}\times\pi\times(0.15\times10^{-3})^2[/tex]

[tex]I=1.97=2.0\ A[/tex]

Hence, The current is 2.0 A.