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48. Given two long (L=1m) parallel wires separated by a distance of 2 cm. Each wire carries 0.5 A in opposite directions. The two wires 1 0 SA 1-0.5A A. exert attractive magnetic forces B. exert repulsive magnetic forces C. exert zero magnetic forces D. none of the above 49. Suppose you try to "lose" the calories gained when eating the "Big Mac meal" by exercising - say by doing an equivalent amount of work in the gymnasium by lifting a 50 kg "weight" a vertical distance of 5 feet (1.54 metre). How much work is expended in lifting the 50 kg weight 5 feet once (1.54m) ? A. 755 J B. 749 J C. 678 J D. 777 J E. none of the above 50. Refer to the following: An object (m=10kg) is initially at rest at point A and starts to move along a frictionless track 200 m 160 m Apply conservation of energy to determine its speed when it reaches point C. Specify point B where PE=0 A. 28 m/s B. 9.8 m/s C. 4.9 m/s D. 32 m/s E. none of the above