Question { 18296 }

difference between ac motor and dc motor

Answer

AC MOTORS: ALTERNATING CURRENT MOTORS
DC MOTORS: DIRECT CURRENT MOTORS
DC MOTORS R SELF STARTING
AC NEED STARTING EQUIPMENT
DC R ONLY 1 PHASE
AC R 1 AND 3 PHASE

Question { SSC, 42453 }

Study of life in outer space is called
A) Endobiology B) Exobiology
C) Entrobiology D) Neobiology

Answer

Exobiology is the right n 100% correct answer
for any doubt visit google.

Question { 9193 }

whats is MARX CIRCUIT?

Answer

IT IS USED WITH GENERATORS FOR CHARGING A NO OF CAPACITORS
IN PARALLEL AND THEN DISCHARGING THEM IN SERIES.
INTRODUCED BY: E. MARX IN 1924.
IT IS USED WHEN VOLT. REQD FOR TESTING IS HIGHER THAN THE
AVAILABLE.
BUT CANNOT USE ABOVE 200KV THE SYSTEM BECOMES BULKY AND
EXPENSIVE.
FOR DAIGRAMS PLZ SEND ME UR EMAIL ID AT
ankushmiglani2000@gmail.com

Question { NTPC, 20358 }

how the inductor will work on dc supply?whether it will
work or not?

Answer

inductor works as a conductor of long length.

Question { 22915 }

WHY IS THE POWER FACTOR NOT MORE THAN UNITY.

Answer

powe factor more than unity is possible but if it is so
the ckt becomes a sorce and starts supplying powr to the
mains
it happened coz the current starts leading voltage by an
angle mopre than 90 deg. and stsrts feeding the mains.

so powerv factor cant be more than 1

Question { 6392 }

AIR GAP IS TERMED AS USEFUL. WHY?

Answer

air gap is harmful not usefull

Question { 10018 }

DOES A MAGNETIC CIRCUIT CONSUMES ENERGY? IF YES, WHY?

Answer

magnetis ckt doesnt cosume energy but it stores energy in
the form of current
its formula is something 1/2 i*iL
dont know the xacty formula`

Question { 4462 }

IN A MAGNETIC MATERIAL HYSTERYSIS LOSS CAN'T BE REDUCED TO
ZERO. HY?

Answer

JUST GO THRU HYSTERISIS LOOP.
IT SHOWS THAT WHEN H DECREASES TO ZERO THE CURRENT BECOMES
NEGATIVE WHICH IS NOT POSSIBLE

SO THE HYSTERISIS LOSS CANT REDUCED TO 0.

Question { 22245 }

How earth resistance reduses by pouring water coal and salt?

Answer

the hard water is one of the good conductor of elecricity
as explained in ship earthing.
the mixing of these things in earth makes the earth
conductive n hence reduces the earth resistance.

Question { Nestle, 17424 }

what is drive speed & what is driven speed

Answer

look the drive speed is wat produced by the source while
the driven speed is wat consumed by the sink.

Question { 3908 }

What is percent age of scrap of wires as per IE Rule Clause
No in wiring for House and Industrial wiring ?

Answer

10%

Question { 4465 }

what perpos use cepacitors in motars,fans,lights,and LT
panal

Answer

dear ac contains +ve and -ve cycles now in wat direction
fan will move.
the capacitor increases the amplitude of +ve cycle by
giving it the stored magnetic energy and fan starts
rotating in +ve directioni.e anticlockwise


do one thing change the connections of capacitor and wat
will u see is tha t the fan starts rotating in opposite
direction


do one more thing remove the capacitor and make the
connections complete without capacitor u see the fan will
not rotates in any direction now take a rod and rotate the
fan manualy in any direction the fan starts rotating

in tubelights it is used toblock the dc component so as tto
avoid noise

in m/cs used as starter

in lt panels used to improve the power factor

Question { 11228 }

Transformer not operated in dc ! why?

Answer

see i will give u the exact answer
in actual wat happn when u apply dc at the primary flux
will be produduced in the core bt it is not alternating in
nature hence no flux is cut by the secondary winding so no
current is there in secondry side
and due to static flux the leakage current produced in the
primary side is high wich starts heating the pr wdg and
finally it burns the pr wdg and t/f is damaged.

so pls never ever try to give dc to a t/f
haan pactically dekhne ke liye try kr b sakte ho bt baad me
mt bolna ki inform ni kiya tha

Question { APC, 4776 }

Why in USA supply voltage parameters(230V,60Hz)are
different,is there any advantage please brief.

Answer

dear in actual wat happn in 19 and 20 century the t/fs and
m/c becoming very popular. these two gives the best o/p at
low frequencies like synchronous generators at 2hz fr.

bt now the transmission lines require high fr to transfer
the voltages without or at minimum loses.

so standards are defined
for high fr low voltage and for low fr high voltage
for a fr of 60 hz only 100-120 v is sufficient
and for 50 hz 200-240 v
some contries adopt the formal one while other adopt the
later one.

now see the case of japan in some area 60 hz is used while
in some area 50 hz is used
jisko jaisa convinient lga us contry ne wohi adopt kr liya

Question { 2746 }

can you give me some names of projects which can be used in
our daily life & which is having medium cost?

Answer

temprature based device controller with data logger
it basically an electronic project consistsof 5-6 ic
suppose u hav eheater, fan, ac
now u set a ref temp say 25 deg
now below 25 deg ur heaterwill starts
from 25-30 deg fan starts
from 31-35 deg ac starts
the data logger stores the various temp value