Esco M

Hi I've been sponsored by a (UK) company to do an industrial Ph.D at my Uni where I completed my undergrad degree in electrical engineering.

I am 33yrs old and would like some advice on the process.

I am an home student

I'm having problem understanding and getting the answers to these question.....

1.) why is it possible to start a small motor directly on-line(DOL) but impractical for large ones.?

2.) why is the motor inefficient at high values of slip?

3.) why does AC Motor draw current even though the slip is zero.?

4.) under no load the motor spins at a speed below the synchronous speed(1500rpm -for a 4 pole motor @ 50 Hz).why is that?

5.) what is the difference between the Slip current in Delta connection to that of the Slip current in Star connection.?

I'm having problem understanding and getting the answers to these question.....

1.) why is it possible to start a small motor directly on-line(DOL) but impractical for large ones.?

2.) why is motor inefficient at high values of slip?

3.) why does AC Motor draw current even though the slip is zero.?

4.) under no load the motor spins at a speed below the synchronous speed(1500rpm -for a 4 pole motor @ 50 Hz).why is that?

5.) what is the difference between the Slip current in Delta connection to that of the Slip current in Star connection.?

a)

An ideal resistor (R= 3Ω),capacitor (C=5nF) and inductor (L=100mH) are connected in series and a sinusoidal voltage of frequency f (Hz) is applied across the combination.

What will be the formula for the impedance Z of the combination. And what frequency f the circuit is at Resonance.

b)

An ideal resistor (R= 2Ω),capacitor (C=100 μF ) and inductor (L=40mH) are connected in parallel and a sinusoidal current of frequency f (Hz) is applied across the combination.

What is the formula for the admittance Y of the combination.

At what frequency f the circuit is @ resonance.

I seems to be stuck on this question,I'll appreciate your help...

Electrical/Electronics problem?

a)

An ideal resistor (R= 3Ω),capacitor (C=5nF) and inductor (L=100mH) are connected in series and a sinusoidal voltage of frequency f (Hz) is applied across the combination.

What will be the formula for the impedance Z of the combination. And what frequency f the circuit is at Resonance.

b)

An ideal resistor (R= 2Ω),capacitor (C=100 μF ) and inductor (L=40mH) are connected in parallel and a sinusoidal current of frequency f (Hz) is applied across the combination.

What is the formula for the admittance Y of the combination.

At what frequency f the circuit is @ resonance.

I seems to be stuck on this question,I'll appreciate your help...

a)

An ideal resistor (R= 3Ω),capacitor (C=5nF) and inductor (L=100mH) are connected in series and a sinusoidal voltage of frequency f (Hz) is applied across the combination.

What will be the formula for the impedance Z of the combination. And what frequency f the circuit is at Resonance.

b)

An ideal resistor (R= 2Ω),capacitor (C=100 μF ) and inductor (L=40mH) are connected in parallel and a sinusoidal current of frequency f (Hz) is applied across the combination.

What is the formula for the admittance Y of the combination.

At what frequency f the circuit is @ resonance.

I seems to be stuck on this question,I'll appreciate your help....................

my seat leon 1.6 on a 56 reg alarm keep going off in the middle of the niight,I didn't drove the car for 2 mths,the battery went flat,so i use a jump leads to start it up,every since then the alarm kept going off in the middle of night around the same time every night.

I take it to a battery testing place,they say the battery is fine,anyway if I don't run the car for a day then the battery will go down.So i replace the battery with brand new bosch type,and the same problem keep occuring with the alarm.

my seat leon 1.6 on a 56 reg alarm keep going off in the middle of the niight,I didn't drove the car for 2 mths,the battery went flat,so i use a jump leads to start it up,every since then the alarm kept going off in the middle of night around the same time every night.

I take it to a battery testing place,they say the battery is fine,anyway if I don't run the car for a day then the battery will go down.So i replace the battery with brand new bosch type,and the same problem keep occuring with the alarm.

Hi,Does anyone have or known anywhere, i can get a discount code for Thomas Cook or Thomson flight.

Are any discount Voucher website i can visit

does anyone here worked for these Airlines and could give me some advice pls.

cheers

are if you are not Ja'can but come from the Caribbean,do you fell proud for Jamaica's at moment for putting the world's eye's on the Caribbean Region for the positivity that the sprinting Greats from Jamaica are doing in Beijing China.

I'm Ja'can living in the UK,and they want to know what we have on the Island that producing so much great athlete,we are conquering the world of sprinting,yet with more world record form Usain "lightinng" Bolt and not to mention V.Campbell and Melaine Walker in the 400m hurdling.

Sarah T....I've taken this qoute from your question that "Jamaica is poverty stricken" let me tell you this and read very carefull.Jamaica is one of the richest place in the Caribbean to live,with place's like Beverly Hills,and yes it's the same has the one in a America.Not to mention Jax Hills,Red Hills,Cherry Gardens,Mona Heights just to name a few.Get a life,are some education,how could you think that Jamaica and Antigua are the same Country,that shows that you ignorant's and lack of knowledge.

Poverty are every where,if everyone was rich,then no one will ever work,could you imagin the world with no one working,a bet you could,cuase it sound like,you don't work,but living of government benifit's.Poverty are in the UK as well if any one watch the show called "Secret Millonaire" you will see what am talking about.

Jamaican people or Caribbean people,it doesn't matter about the little that we have,our Culture and our atmosphere will always be on top......big up all Ja'can..weh me sey No Linga...I man stop drink White Rum,A straight Appleton Gold me a drink................bless

For the all people who say's Jamaica is a bad place to live. I have some Questions for you.With all the stabbings in London and all over the UK.Are you scared of your life when walking in the streets of London at night.With some news paper saying dont go south of the River Thames,and some Europeon countries warning their Citizen dont go to the UK.How do you fell about that? Because as something happen in Ja every one who's NOT Ja'can quick to stay how bad and dengerous our Proud lovely Island of Ja is,look in your own back yard first before you slag off other countries.Look at the two French student who got killed for their play station,if that did happen in Jamaica,the media and the whole of England would be telling people not to go Jamaica,so why,are they not telling people dont go to London.Jamaica get one million British tourist each year,so dispite what ever they are saying about our country,we are the number one Caribbean destination for the Brit's.

Anyone been to trelawny beach in Falmouth,and if so what's it like,am going there in December........One more ting are Trelawny Beach,and, Starfish Trelawny are their both the same resort?

Did anyone lived in the North Nottinghamshire area, feel the earthqauke at about 00.57 hrs and lasted for about 30 seconds,if so, what was your experience,did you felt scared?

I would like to know IF, Trelawny Beach in falmouth Jamaica is the same as Starfish Trelawny.and if it is,has anyone stayed there and how's it,am thinking of going there for holiday,but am a bit confuse,cause some website says Trelawny Beach and some says Starfish Trelawny.....

Hello i have recently completed an HND in Electrical Engineering,am applying for jobs,every job i apply for,they told me i haven'nt got any experince,can someone tell me where to go, to get some experience or apprentiship trainning, i live in the Nottingham arera or any company in Nottingham employing graduates in Electrical Engineering

Hello i have recently completed an HND in Electrical Engineering,am applying for jobs,every job i apply for,they told me i haven'nt got any experince,can someone tell me where to go, to get some experience or apprentiship trainning, i live in the Nottingham arera or any company in Nottingham employing graduates in Electrical Engineering

Hello i have recently completed an HND in Electrical Engineering,am applying for jobs,every job i apply for,they told me i haven'nt got any experince,can someone tell me where to go, to get some experience or apprentiship trainning, i live in the Nottingham arera or any company in Nottingham employing graduates in Electrical Engineering.

Hello i have recently completed an HND in Electrical Engineering,am applying for jobs,every job i apply for,they told me i haven'nt got any experince,can someone tell me where to go, to get some experience or apprentiship trainning, i live in the Nottingham arera or any company in Nottingham employing graduates in Electrical Engineering. ( ideally i would like to work for Rolls-Royce)

hello,i've finish college and gain an HND qualification in Electrical Engineering,i want to know where can i get the experence to work in this fleid, in Nottingham area,cause every job i see in the papers they actually want some one with 5 or more yrs experience.

hello,i've finish college and gain an HND qualification in Electrical Engineering,i want to know where can i get the experence to work in this fleid in the Nottingham area,cause every job i see in the papers they actually want some one with 5 or more yrs experience.