Magnetism:magnetitude of mag field

[Dx]

Hi!
calculate the magnitude of the magnetic field at the center of a solenoid which has 100 turns, is .1m long and carried a current of 1A?


n = N/l = 100/.1 = 1K then
B= uo * n * I = 4PI x 10^-7 * 1K * 1A = 1.257x10^-3

why is this wrong?
dx

 

[quantumdude]

It's correct. Maybe your professor made a mistake?

 

[Dx]

Originally posted by Tom
It's correct. Maybe your professor made a mistake?

you know I am about to say something; he has these interns who also mis grade my darn test which has got me pummling for hours trying to find out what my mistake was. This is not cool; its borderline injustice to the class I say. Just teasing but I think they should take more emphasis on grading that could be the determining factor of a passing or failing grade, you know?
Thanks Tom,
Dx

 

[arcnets]

Originally posted by Dx
why is this wrong?

Hi Dx,
sorry you have so much trouble. Just noticed your answer doesn't have a unit (should be Tesla). Maybe that's why your prof. marked it wrong...