FINAL EXAM CRN 12517 (L 52) 31stDecember, 2013 Exam duration: 3 Hours Marks: 30 Instructions:Use the space to explain your answer and no loose papers will be allowed. Use back of the page if you need more space. Write your answers systematically including every steps of your calculation.Write your final answer with specific significant digit and do not forget to write the units. Full points will be awarded only if all steps and correct units are written. Useful Equations:

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Theory Part (5 points) 1.The source of generation of Earths magnetic field is _________ (A) Magnetic monople (B) Magnetic dipoles (C) Spinning of electrons (D) Iron and cobalt (E)Earths Core Student Name: . . . . . . . . . . . . . . . . . . . . . . . . . . . .Student ID: . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.What causes a compass to behave as it does? (A)Earths gravity (B)Earths shape (C)Earths geographic north pole (D)Earths magnetic field 3.Which circuit is represented by the frequency response curve in the given figure? 1mark (A)High-pass filter (B)Low-pass filter (C)Band-stop filter (D)Band-pass filter

4.A220V,150Vbulbisconnectedinserieswiththeprimaryofa220/1,100V,50Hz transformer.Iftheloadonthesecondarysideisdisconnected,thebrightnessofthebulb will (A)Increase (B)Decrease (C)Decreases to a very low value (D) Be Unaffected 5.Transformer changes the value of (A)Power (B) Frequency (C)Voltage and Current (D)Voltage (E)Current RLC Resonant Experiment [12.5 Points] 1.By Using the following table starting from the resonant frequency [6points] f() VinVoutGain ( ) fo- 200= fo- 100= fo= fo +100= fo +200= 2.Plot Graph by using the table above to plot versus f on a graph paper,(i.e.f on the X-axis, and along the Y-axis).Do not forget to put the titles and units on the axes.[3 points] 3.UsetheabovetabletodeterminethecapacitanceoftheunknowncapacitorC, Usethenecessaryformulaegivenonfirstpage.Giventhecircuitthatisusedto studytheRLCcircuitbehavior.Thevalueoftheloadresistanceis10.00.1, whiletheinductanceisdependingonthecoilgeometrygivenvalueofL= 0.5mH.[3.5 points] Earth Magnetic Field[12.5 Points] 1.Setthecurrentatthevalueslistedinthetablegivenbelowandmeasurethe corresponding needle deviation angle (the current values may be change if they are not suitable for your setup). Estimate the error onand .[5 points] 2.Plot your data,on the Y-axis and on the X-axis, using Excel; do not forget the units and titles. [3.5 points] 3.Whenthecurrentflowingthroughacircularcoilof12.5cmX12.5cmis0.15A, andthiscoilhas30turns.ThenthehorizontalintensityBhofearthsmagnetic fieldforthecasewhenthemagneticneedleisdeflectedbyanangleof35ois.(Justify your answer by using formula given).[4 points] Tan() 0.10 0.15 0.25 Extra Page