What Is the Magnitude of B for a Current-Carrying Wire in a Magnetic Field?

[Ry122]

A straight wire of length 90 cm carries a current of 60 A and makes an angle of 45 degrees with a uniform magnetic field. If the force on the wire is 2.0 N what is the magnitude of B.

my attempt:
F=BIL
2=B(6)(.90)
B=.37
What am i doing wrong?

 

[rock.freak667]

F=BIL is assuming the conductor is at 90 degrees to the magnetic field.

if it is at an angle $\theta$, then the formula becomes $F=BILsin\theta$

 

[nlightner]

Your calculation is correct, but you need to convert the length of the wire from centimeters to meters to match the units of current (A) and magnetic field (T). So the correct calculation would be:

F = BIL
2 = B(60)(0.9)
B = 2/(60*0.9) = 0.037 T

Alternatively, you could also convert the current from amperes to milliamperes (mA) to match the units of length (m) and magnetic field (T). The calculation would be:

F = BIL
2 = B(0.06)(0.9)
B = 2/(0.06*0.9) = 37 T