A 0.15-m straight wire moves with a constant velocity of 7.0 m/s perpendicularly through a magnetic field. If the magnetic field has a strength of 0.40 T, what is the
electromotive force?

force is 0.42 N

Explanation: F = l·v·B

c

explanation:

the box does not move because you need to use a force greater than 300 n. you are only using 50 n. it needs to at least be 301 n for the box to move because then it is an unbalanced force and it will move the way that the greater force is pushing it. if you use only 300 n it will be a balanced force and will not move because the force you are exerting on the   box is the same as its force.

hope this !

im sorry if i went too in depth, i am going to include a link to a video on khan academy that will explain this.   hope that you like the video and that it explains more in detail to you.

that is the link.