An electromagnetic tug is a proposed orbital device consisting of some solar panels, a long- rigid...

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An electromagnetic tug is a proposed orbital device consisting of some solar panels, a long- rigid framework holding two parallel conductors in place. To be clear, this device is already in orbit, assembled from parts placed there by some other means. One conductor is exposed to the Earth's magnetic field while the other is shielded. An electrical current is run down one conductor and back through the shielded conductor. Calculate the force acting on a long straight wire 1 kilometer long carrying 10 amps of current. The conductor is orientated perpendicular to the surface of the Earth. Assume the local magnetic field in low earth orbit is 35000 nT and orientated due north. Let the entire apparatus mass 2000 kg. What acceleration does the apparatus experience? Note: Vectors, such as acceleration, have both a magnitude and a direction. Evaluate the potential of an electromagnetic tug to operate in low and near-earth orbits. 1. Key Idea: Write down a short statement of the physical principle which you think is the most relevant to solving the problem, and what ideas and tools you intend to use with this principle. PREPARE: 2. Stock of Data: SOLVE: a. Given: Make a list of the numerical data you are given in the problem description. Be sure to include units. b. Unknowns: List quantities you are asked to calculate. 3. I.D. Equation: Choose an equation which reflects both the key idea of your problem and information from your stock of data. You may need more than one equation. 4. Solve algebraically: If the equation or equations you have chosen are not already solved for you unknown then do the algebra to accomplish this now. Be sure to show enough detail in each step so that a reader can follow your work. 5. Substitute in Numerical Data: Once you have an analytic solution, substitute numerical values into the analytic solution to obtain the final answer. Do not combine the Solve and substitute steps. Treating numerical quantities algebraically, e.g. moving them around, is a major source of miscopied numbers and dropped units. ASSESS: 6. Accuracy and precision: Make sure your solution answers the question asked, and includes the correct units and number of significant figures. 7. Sanity Check: Answer the question. "Does this answer make sense in light of the rest of the knowledge I possess?" The algebraic solution you arrived at in the Solve step is one of the more powerful tools you can use for a sanity check. The sanity check could also include a back of the envelope calculation done with a single significant digit or a unit analysis of the final answer. (Note: One Sanity-Check is sufficient.) Refer to the example below, and look at Examples in the textbook for more on the Assess process. 1 An electromagnetic tug is a proposed orbital device consisting of some solar panels, a long- rigid framework holding two parallel conductors in place. To be clear, this device is already in orbit, assembled from parts placed there by some other means. One conductor is exposed to the Earth's magnetic field while the other is shielded. An electrical current is run down one conductor and back through the shielded conductor. Calculate the force acting on a long straight wire 1 kilometer long carrying 10 amps of current. The conductor is orientated perpendicular to the surface of the Earth. Assume the local magnetic field in low earth orbit is 35000 nT and orientated due north. Let the entire apparatus mass 2000 kg. What acceleration does the apparatus experience? Note: Vectors, such as acceleration, have both a magnitude and a direction. Evaluate the potential of an electromagnetic tug to operate in low and near-earth orbits. 1. Key Idea: Write down a short statement of the physical principle which you think is the most relevant to solving the problem, and what ideas and tools you intend to use with this principle. PREPARE: 2. Stock of Data: SOLVE: a. Given: Make a list of the numerical data you are given in the problem description. Be sure to include units. b. Unknowns: List quantities you are asked to calculate. 3. I.D. Equation: Choose an equation which reflects both the key idea of your problem and information from your stock of data. You may need more than one equation. 4. Solve algebraically: If the equation or equations you have chosen are not already solved for you unknown then do the algebra to accomplish this now. Be sure to show enough detail in each step so that a reader can follow your work. 5. Substitute in Numerical Data: Once you have an analytic solution, substitute numerical values into the analytic solution to obtain the final answer. Do not combine the Solve and substitute steps. Treating numerical quantities algebraically, e.g. moving them around, is a major source of miscopied numbers and dropped units. ASSESS: 6. Accuracy and precision: Make sure your solution answers the question asked, and includes the correct units and number of significant figures. 7. Sanity Check: Answer the question. "Does this answer make sense in light of the rest of the knowledge I possess?" The algebraic solution you arrived at in the Solve step is one of the more powerful tools you can use for a sanity check. The sanity check could also include a back of the envelope calculation done with a single significant digit or a unit analysis of the final answer. (Note: One Sanity-Check is sufficient.) Refer to the example below, and look at Examples in the textbook for more on the Assess process. 1