Magnetic fields and sodium ions

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AznBoi
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Homework Statement


Sodium ions (Na+) move at 0.851 m/s through a bloodstream in the arm of a person standing near a large magnet. The magnetic field has a strength of 0.254 T and makes an angle of 51 degrees with the motion of sodium ions. The arm contains 100 cm^3 of blood with 3 x 10^20 Na+ ions per cubic centimeter. If no other ions were present in the arm, what would be the magnetic force on the arm?


Homework Equations



[tex]F_{B}=qvBsin\theta[/tex]


The Attempt at a Solution



First I found charge by doing some mathematical operations:
[tex]100 cm^{3} * \frac{3*10^{20} Na+ ions}{cm^{3}}[/tex]
[tex]= 3*10^22 Na+ ions * (1.60*10^{-19})[/tex]
[tex]=4800 C[/tex] <--- I'm not sure if this procedure is right.

If the charge is correct, then: [tex]F_{b}=4800 (0.851 m/s)(0.254 T)sin 51[/tex] [tex]=806.32 N[/tex]
 
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Also, although this is irrelevant and not associated with the problem above, what is the charge of a "singly charged ion" with mass= 2.18 x 10^-26kg? Thanks.
 
AznBoi said:
Also, although this is irrelevant and not associated with the problem above, what is the charge of a "singly charged ion" with mass= 2.18 x 10^-26kg? Thanks.
The assumption is that the ion has a charge of the fundamental charge, [itex]e[/itex] (charge on a proton or electron). This has a value of 1.60 x 10^-19 C. [itex]Na^+[/itex] is a singly charged ion.