Recent content by mikehsiao789

Thanks guys! I was confused because I searched through my textbook and it said that the no-load test was only for the AC machines and didn't mention anything about the DC. Hence, I used those equations I found on Wikipedia. I assumed that for a locked rotor test, the w would be 0. so V=RIa and...

Homework Statement A locked rotor test is performed on a permanent magnet DC machine with the following results: Terminal Voltage 5 V DC Input Current 10 A DC Locked rotor torque. 20 Nm a) Making suitable approximations deduce the effective rotor resistance in ohms? b) Making suitable...

Homework Statement A short circuit test is performed on a small single phase transformer. The results are: Primary Voltage 5V, 60Hz Primary Current 2A Secondary Current 10A Primary Power 8W a) Making suitable approximations deduce the primary/secondary turns ratio (single number)? b) Making...

I realized I made a mistake, the impedance should we Z1= 10 + j*60*2pi*10^-3 and Z2 remains the same... which would give me a Zeq of: 5.171+ j0.91. Umm, if I had a 60 Watt resistive load on the secondary side, with 120V, the current on the primary side must be 0.5A, which means the load would...

Homework Statement In the circuit shown the 120V, 60Hz source supplies the ideal load shown through an ideal 2:1 transformer. What steady state current would you expect to read on the rms ammeter shown (please find the picture attached)? Homework Equations Zeq = (1/Z1+ 1/Z2)^-1 Z1 =...

Hello, I've been stuck on this question for a few hours and I hope someone can help. Here is the question: "Consider two materials bismuth and aluminum with χ m = −20 ×10−5 and χ m = 2 ×10−5, respectively. Find the magnetization vector and the magnetic field in these materials when they are...

Find the solution of y"=-k^2*y , y(0)=1 y'(0)=0? Homework Statement Find the solution of y"=-k^2*y , y(0)=1 y'(0)=0? Homework Equations y"=-k^2*y , y(0)=1 y'(0)=0? The Attempt at a Solution I've been stuck on this problem for a while but I can't seem to get it. I used the method...

Homework Statement Hello, I have been given a list of functions and I need to figure out if they are linearly dependent or not. I've been trying to solve the problems for a while but I cannot figure out which ones are wrong. The list of functions are on my webpage at...

Homework Statement I need to find the current through the 3V voltage source: picture of the circuit and the equations there: vantraveller.blogspot.ca The Attempt at a Solution I was about to get 3 equations, however, I find myself having 5 unknowns, what other equations can I write...

I tried a new design, and here it is: http://vantraveller.blogspot.ca/. Do you think this would provide a right measure of beta?

What I am confused about is, for a PNP transistor, because the current is coming out from the base, is it right to put a current source to keep the current to 0.1mA? If it is, and I have 1n4148 diodes and resistors to make it, how would I make a current source of of the Base current to keep the...

oops sorry, new to this site, not sure if I posted in the right section. Been stuck on this problem for the past 20 hours... haha

Hello, I am trying to design a circuit that can measure the BETA of a PNP and NPN transistor, I have an ammeter, and I have a design that makes IB going in 0.1mA, so that the current IC of the collector with a shifted decimal is the Beta we would like to measure. So I used a current source, and...