A wire along the z axis carries a current of 4.9 A in the +Z direction. Find magnitude of the force exerted on a 3.3 cm long length of this wire by a uniform magnetic field pointing in the -x direction having a magnitude 0.43 T

   F = - 6.95 10⁻² j^  N

Explanation:

The force on a wire carrying current through a magnetic field is

         F = i L x B

The bold letters indicate vectors, as the wire is in the positive Z axis and the magnetic field in the negative x axis, the force must be in the negative y axis

the force module

            F = i LB

that there is 90º between the two vectors and the sin 90 = 1

let's calculate

            F = 4.9  3.3 10⁻² 0.43

            F = 6.95 10⁻² N

the force vector is

           F = - 6.95 10⁻² j^  N

i think it's 35 meters

what experimental evidence led scientists to change from the previous model to this one?

a few of the positive particles aimed at a gold foil seemed to bounce back.

the colors of light emitted from heated atoms had very specific energies.

experiments with water vapor showed that elements combine in specific proportions.

cathode rays were bent in the same way whenever a magnet was brought near them.