A wire of length 0.50 m carries a current of 0.10 A in the positive x-direction, parallel to the ground. If the wire has a weight of 1.0 _ 10_2 N, what is the minimum magnitude magnetic fi eld that exerts a magnetic force on the wire equal to the wires weight? (a) 0.20 T (b) 0.30 T (c) 0.40 T (d) 0.50 T (e) 0.60 T

Conservative energy - The work it does is stored in the form of energy that can be released at a later time - Gravity - Spring force Non conservative energy - Work done cannot be recovered later as kinetic energy; instead, it is converted to other forms of energy - Friction - Tension in a rope Conservative force - A force that does zero total work on any closed path - Work done by friction on a closed path is not zero o = ∙ = - Work done by gravity on a closed path is zero o = ∙ = - The force is conservative if the work done by a force in going from an arbitrary point A to an arbitrary point B is inde