# Question

A beam contains 2.0 x 108 doubly charged positive ions per cubic centimeter, all of which are moving north with a speed of 1.0 x 105 m/s. What are the

(a) Magnitude and

(b) Direction of the current density J?

(c) What additional quantity do you need to calculate the total current i in this ion beam?

(a) Magnitude and

(b) Direction of the current density J?

(c) What additional quantity do you need to calculate the total current i in this ion beam?

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