Find magnetic field strength and maximum force

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warnexus
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Homework Statement



Online homework screenshot showing a wire carrying 14 A at 27 degrees to a uniform magnetic field, with force per unit length 0.28 N/m; Part A asks for field strength in mT with entry 4 and a Try Again message; Part B asks for maximum force per unit length, left blank.


Homework Equations



Force = Current * Length * Field Strength * sin(theta)

(Force/ Length)/(Current * sin theta) = Field Strength



The Attempt at a Solution



(.28 N/m)/ (14 A * sin 27 degree) = .044 T or 44mT
 
haruspex said:
The 'try again' image seems to indicate the answer you entered was 4, not 44.

thanks. apparently I did not see the milli Tesla and when I rounded my answer it threw my answer off . how do I go about finding a maximum force? how do I know if the force I got is actually maximum?
 
Maximum force possible is when wire is perpendicular to magnetic field. sin90 = 1, biggest possible. sin (other angles) will result in a smaller answer.

So maximum force is BIL (B-magnetic field strength, I-current, L-length [full length as totally perpendicular]) B is your previous answer.
 
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