Draw a suggestion for a measuring set-up to find the self-inductance L. Assume that L =...

 

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Draw a suggestion for a measuring set-up to find the self-inductance L. Assume that L = 40 mH and draw the expected time course for the voltage across the inductor and the current in it. You will now use measurements to find the self-inductance of an inductor. The inductor is not ideal and must therefore be represented as an ideal inductor in series with a resistor (including will the windings in the inductor have a certain resistance). The resistance is relatively small and it is assumed that it is less than 100 N. By connecting large resistors in series with the inductor and apply a triangular voltage one can perform measurements on current and voltage in the circuit that makes one find the inductor self-inductance L. Here is a useful connection to use that the voltage measured across the inductor is: VL = L (diL/ dt) + iL RL, where VL is the voltage across the inductor, iL is the current through the inductor and RL is the resistance inside of the inductor. Find the inductors self-inductance L by starting from a triangular signal voltage with a frequency f 1 kHz, a resistor of 15 kohm and an oscilloscope. Take a picture of the voltage across the inductor and the current in it as a function of time. Explain how you can calculate L from this screen and perform the calculation. Can you see from the screen that the inductor contains a resistor? Calculate the value of this resistance. The moment you get a jump in the voltage across the inductor, you get an unexpected, short-lived one interference with the signal. Show an enlarged section of this disorder. Can you explain what this is coming from? The inductor is not shielded from environmental influences. Can you see any electrical noise on the voltage across the inductor? Check the inductor inductance L when measuring with an RLC meter. Draw a suggestion for a measuring set-up to find the self-inductance L. Assume that L = 40 mH and draw the expected time course for the voltage across the inductor and the current in it. You will now use measurements to find the self-inductance of an inductor. The inductor is not ideal and must therefore be represented as an ideal inductor in series with a resistor (including will the windings in the inductor have a certain resistance). The resistance is relatively small and it is assumed that it is less than 100 N. By connecting large resistors in series with the inductor and apply a triangular voltage one can perform measurements on current and voltage in the circuit that makes one find the inductor self-inductance L. Here is a useful connection to use that the voltage measured across the inductor is: VL = L (diL/ dt) + iL RL, where VL is the voltage across the inductor, iL is the current through the inductor and RL is the resistance inside of the inductor. Find the inductors self-inductance L by starting from a triangular signal voltage with a frequency f 1 kHz, a resistor of 15 kohm and an oscilloscope. Take a picture of the voltage across the inductor and the current in it as a function of time. Explain how you can calculate L from this screen and perform the calculation. Can you see from the screen that the inductor contains a resistor? Calculate the value of this resistance. The moment you get a jump in the voltage across the inductor, you get an unexpected, short-lived one interference with the signal. Show an enlarged section of this disorder. Can you explain what this is coming from? The inductor is not shielded from environmental influences. Can you see any electrical noise on the voltage across the inductor? Check the inductor inductance L when measuring with an RLC meter.