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paul1

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done the test the other day any ideas on theses answer, so i know where ive went wrong

1. Cage rotor indusction motors are condidered to be?

varaible speed machines

low speed machines

high speed machines

constant speed machines

2.if the plates of a parrelle plate capacitor are increased in area, then the capacitor will ?

not change

increase

decrease

recieve to 0

3. an example or overload current is one which flows in a circuit?

phase-earth fault

phase-neutruel fault

due to open circuit

when motor starts

4. in a 4 pole 50hz induction motor the sychorous speed will be?

50rs

25rs

16.66rs

12.5rs

5 in a switch (glow) stat floursecent circuit, the 2 reasons for the choke in the circuit are?

powr factor correction and effincy

high voltage starting and current lumination

high voltage starting and improve effincy

current lumminares and powr factor correction

 
1. Cage rotor indusction motors are condidered to be?

varaible speed machines

low speed machines

high speed machines

constant speed machines

2.if the plates of a parrelle plate capacitor are increased in area, then the capacitor will ?

not change

increase

decrease

recieve to 0

Capacitance?

3. an example or overload current is one which flows in a circuit?

phase-earth fault

phase-neutruel fault

due to open circuit

when motor starts

4. in a 4 pole 50hz induction motor the sychorous speed will be?

50rs

25rs

16.66rs

12.5rs

5 in a switch (glow) stat floursecent circuit, the 2 reasons for the choke in the circuit are?

powr factor correction and effincy

high voltage starting and current lumination

high voltage starting and improve effincy

current lumminares and powr factor correction

 
No 1. cage rotor motor you have no control of the induced current so they are considered constant speed

No 2. The capacitance will increase (same as connecting them in parrallel)

No 3. option 1 & 2 are short circuit faults,, open circuit will have no current, motor start up will cause a higher than usual current (over current)

N0 4. Frequency divided by number of pairs of poles = revs/sec

No 5. It won't increase efficiency as the choke is an inductive load and will cause the current to lag voltage, I guess option 3 should read high voltage starting and current limitation and that would be correct

 
got mine in 2 weeks did these come up in the exam can you remember any more ?

 
got mine in 2 weeks did these come up in the exam can you remember any more ?
yes mate i failed it i got 81% on the health and safety snd 41% on the other part.

them question came up and are the ones i can remember

there was alot of questions on motors so start revising them

 
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