Question

A 10m wire that carries a current of 3A from east to west is placed in a magnetic field of 0.0004T running from south to north. Find the size and direction of the magnetic force on the wire.

**how do we find this? :/ Thanks!!:)

Answer 1

the situation described into your problem is:

Answer 2

ok!

Answer 3

since magnetic field and current are perpendicular each other, then the magnitude of the magnetic force is:
\[\Large F = ILB\]
where L = 10 meters

Answer 4

yes:)

Answer 5

namely:
\[\Large F = ILB = 3 \times 10 \times 4 \times {10^{ - 4}}\]

Answer 6

ok so we get 0.012?

Answer 7

yes! correct the unit of measure is Newtons, so we have:
F= 0.012 Newtons

Answer 8

is that the size of the force? :/

Answer 9

yes!
now the direction is given by the rule of product vector, so the orientation of the magnetic force is like below:

namely the vector F is perpendicular to both current and magnetic field, and it is oriented inward of the drawing plane

Answer 10

ok! so it is going south?

Answer 11

no, it is going inward of the drawing plane, here is a 3-D view:

Answer 12

ohh so it is going northeast?

Answer 13

no, that is a 3-D view not a 2-D view

Answer 14

ohh i am confused then haha what direction is that ? :/

Answer 15

it is perpendicular with respect to North-South direction and it also is perpendicular with respect to West-East direction

Answer 16

ohh okay :/ wow confusing hahah :P thank you!! so this problem is complete?

Answer 17

yes!

Answer 18

yay thank you1!:D

Answer 19

:)