Directions: Show the steps required to arrive at the answer. Work out the problems on separate page. 5.3 , Magnetic Force on a Current-Cagying Wire 1. What is the direction of the magnetic force on the current in each of the six cases? on... | 1x1! ' I XXI l'l III. - I I I U... ..,., :II II:'. " '9 _ 2. Suppose two long straight wires run perpendicular to one another without touching. Does one exert a net force on the other? If so, what is its direction? Does one exert a net torque on the other? If so, what is its direction? Justify your responses by using the right hand rules. 3. Four horizontal wires are arranged on vertical poles, as shown. The wires are equally spaced and have equal currents I in the directions indicated. The dots represent four charged moving dust particles. The sign of the charge on each particle and its direction of motion are shown. Which of the dust particles has a magnetic force exerted on it in the downward direction at this instant? Justify your answer. -.'--.'- 4. The hot and neutral wires supplying DC power to a light-rail commuter train carry 800 A and are separated by 75.0 cm. What is the magnitude and direction of the force between 50.0 m of these wires? 5. The force per meter between the two wires of a jumper cable being used to start a stalled car is 0.225 N/m. (a) What is the current in the wires, given they are separated by 2.00 cm? (b) Is the force attractive or repulsive? 6. A 2.50m segment of wire supplying current to the motor of a submerged submarine carries 1000 A and feels a 4.00-N repulsive force from a parallel wire 5.00 cm away. What is the direction and magnitude of the current in the other wire? 1 = 15.0 A 7. The figure to the right shows a long straight wire near a rectangular current 7.50 cm loop. What is the direction and magnitude of the total force on the loop? 8. a) What is the maximum torque on a 150-turn square loop of wire 18.0 cm 10.0 cm on a side that carries a 50.0-A current in a 1.60-T field? 2 - 30.0 A b) What is the torque when o is 10.90? 30.0 cm 8. Find the current through a loop needed to create a maximum torque of 9.00 N.m. The loop has 50 square turns that are 15.0 cm on a side and is in a uniform 0.800-T magnetic field. 9. Mass m=1.00 kg is suspended vertically at rest by an insulating string connected to X X X X a circuit partially immersed in a magnetic field as shown. The magnetic field has X magnitude B= 2.00 T and the length 1= 0.500 m. X B X X XXX X X a) Find the current I. X X X b) If & = 115 V, find the required resistance R. M + R E m 10. A proton has a magnetic field due to its spin on its axis. The field is similar to that created by a circular current loop 0.650 x 10-15 m in radius with a current of 1.05 x 104 A (no kidding). Find the maximum torque on a proton in a 2.50-T field