A1.2 m wire carries a current of 10.0 a in a uniform magnetic field of 0.050t. find the magnitude of the magnetic force on the wire.

Ok so you want to use the following formula which corresponds to the magnetic force on a wire F = (B)(I)(L) (where L is usually represented by a small l but it looks like I which corresponds to current).

Ok so we need to know what all the letters stand for F of course is the magnetic force. B is the magnetic field strength ( 0.050 T). I is the current (10 A) and L is the length (1.2) of the wire where the magnetic force has an affect. Slot this into your equation and you're done.

F = (0.050)(10)(1.2)
   = 0.6 N (Newtons
Hope this helps :).