Astraight wire carrying a 3.30-a current is placed in a uniform magnetic field of magnitude 0.272 t directed perpendicular to the wire. (a) find the magnitude of the magnetic force on a section of the wire having a length of 12.7 cm. n (b) explain why you can't determine the direction of the magnetic force from the information given in the problem

F = 0.114 N

Explanation:

a) The magnetic force is given by the equations

    F = q v x B = I Lx B

the bold incate vector.  This equation can be used in the form of magnitude and find the direction separately with the rule of the right hand

    F = i L B sin θ

Where θ is the angle between the direction (L) and the magnetic field, if the two are perpendicular sin 90 = 1

Let's calculate

    F = 3.30 0.127 0.272

    F = 0.114 N

b) to know the direction of the magnetized field we must know the direction of B and L, but in the problem they tell us that they are perpendicular, but not the direction of each

lexy is right because she has the labeled s

see the picture for the vector

the magnitude of the vector by pythagorean theorem

r = √( (-10)^2 + (3)^2 ) = √109

magnitude = √109 units

the direction angle between vector and x-axis is

tan^(-1)(3/10) = 16.699

so the direction is approximately 16.7 degrees north of west