A proton beam that carries a total current of 1.3 mA has 10.0 mm diameter. The current density in the proton beam increases linearly with distance from the center

This is expressed mathematically as J(r) = J0 (r/R), where R is the radius of the beam and J0 is the current density at the edge. Determine the value of J0. A) 25 A/m2
B) 6.2 A/m2
C) 12 A/m2
D) 17 A/m2


A

Physics & Space Science

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