Magnitude of the Magnetic Force?

Question

an electric power line carries a current of 1400 A in a location where the earth's amgenetic field is . the line makes an angle of 75 degrees with respect to the field. determine the magnitude of the magnetic force on a 120-m length of line.

i know the answer is 8.1 N. i just need to know how to get there step by step. also if you can do it yourself on the calculator.

i did 1400A * 5.0 x 10^-5 T * 120 * sin(75) = -3.257

Answer 1

LOL change your calculator from radians to degrees :P

In degrees mode it gives the correct answer, the wire is 75 degrees from the magnetic field, not 75 radians :P

Unfortunately this is a common mistake we all make, be careful in tests.

Degree answer: 8.1137

Radian answer: -3.2584

Your working is correct so ;)