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Electrical Engineering

Basics problems of Induction motor

The frequency of the induced rotor currents in the rotor of a 60 Hz induction machine is 2 Hz. Furthermore, the fields in the air gap turn at -40 rpm with respect to the rotor. (a) Find the number of poles. (b) Find the slip of the motor. (c) Find the synchronous speed in rpm. (d) Find the motor speed in rpm. (e) Is this a

Diode DC Models: calculating current and diode parameters

1) Two identical diodes are connected in series with 100 ohms and a 2 V battery such that each diode is forward biased. Let Io = 10fA; n = 1, T = 25 degrees C. Calculate the loop current if (a) ideal diodes are assumed; (b) VD = 0.6 V for each diode; (c) each diode is represented by a piecewise-linear model that is exact at ID

Verifying Voltage Measurement

The circuit shown in the attached figure was built in the laboratory and V0 was measured to be 6.25V. Verify this measurement using the voltage divider principle, whether measured result is consistent with the figure.

Current through the inductor

A security alarm for an office building door is modeled by the circuit as shown in the attachment. The switch represents the door interlock, and V is the alarm indicator voltage. Find the current through the inductor, iL(t), for t>0. The switch has been closed for a long time at t=0.

Sketch the dependence of l versus h on cartesian axes.

The distance l from a point at a height h above the Earth's surface to the horizon can be approximated using Pythagoras theorem by the expression: l = h * SQRT(1 + (2*re/h)) , where re is the radius of the Earth. (a) Sketch the dependence of l versus h on Cartesian axes. (b) Thus determine approximations for l by taking l