Finding the Start-up Torque for a Shunt-wound Motor

I am having difficulty determining the start up torque for the motor. If you could also explain how to do the other parts that would be great. Thanks

Calculating Impedance and Current in a circuit

For the circuit attached, calculate the combined impedance of the 160 uh inductor and 10uf capacitor; and i(t) when Vs(t)=20 cos (wt+pi/4) V when w=25 Mrad/s in both instances. (Circuit is on attached file)

To find the inductor current in a switched circuit a long time after the switch is open.

A security alarm for an office building door is modeled by the circuit shown. 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. This was actually a problem posted by one of the students and I ...continues

The energy stored by a 1 mf capacitor.

Problem also in attached file. The energy stored by a 1 mf capacitor used in a laser power supply is given as W=4e(-10t) J for T>=0. what is the capacitor current at T=0.1s. A) -0.271 KA B) -0.271 A C) 0.271 A D) 1.472 A

Energy stored by a 1 mf capacitor. Find the capacitor voltage.

Problem also in attached file. The energy stored by a 1 mf capacitor used in a laser power supply is given as W=4e(-10t) J for T>=0. find the capacitor voltage at T=0.1 sec. A) 0.60V B) 1.5V C) 54.2V D) 89.4V

Determine the Thevenin equivalent resistance (Rt) of the circuit within the box.

A resistor, R, was connected to a circuit box as shown. The voltage, V, was measured. The resistor was changed and the voltage was measured again. The results are shown in the table. Determine the Thevenin equivalent resistance (Rt) of the circuit within the box. See attached file for full problem description.

Determine v(t) for the sinusoidal voltage described

Problem also in attached file. A sinusoidal voltage has a maximum value of 100V, and the value is 10V at t=0. The period is T=1ms. Determine v(t) for the sinusoidal voltage described. A) 100 sin (3.14t + 0.1)v B) 100 sin (6.28t + 6)v C) 100 sin (3142t + 6)v D) 100 sin (6283t + 0.1)v I arrived at "letter C"

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 ...continues

Diode & transistor models

Can't solve ID = - 4(VGS - 2.5)^2 (mA).

current mirrors

Two transistors used in a current mirror are characterized by βdc = 40, Vo = 0.7 V and RBB = 10k ohms, If R1 = 2.5k ohms, RC = 2k ohms, and VCC = 7.5 V, find VCE and IE for both transistors. I couldn't find the base current to solve the for Vce and IE.