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A wave has a frequency of 250 hertz what is the period of the wave

In which material does sound travel the fastest

In this type of wave particles of the medium vibrate perpendicularly to the direction of the wave itself

A 5 ohm resistor a 10 ohm resistor and a 15 ohm resistor are connected in series to a 120 volt power source What is the amount of current flowing between the 5 ohm resistor and the 10 ohm resistor

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Q: What factors determine the number of poles in a DC machine?
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Why is the number of poles of stator and rotor same in induction machine?

The number of poles on stator and rotor is always the same. If they are not equal?æno torque will be produced, thus, the machine will not function.?æ

Relate the frequency of the generated voltage to the speed of the machine and the number of poles?

N=120f/P where N - number of rotations in rpm f - frequency in Hz and P - number of poles

Why the no of poles are less in induction machine compared to synchronous machine?

The number of poles determines the speed a machine has to turn (RPMs). The more poles, the slower the machine can turn. I don't believe your statement is true. I've seen synchronous generators, for example, that turn at 1200 RPMS, and induction motors that turn at ~1800RPMs.

How is The RPM of an electric motor is determined?

The two main factors are the frequency and the number of poles of the motor. A formula for RPM is HZ x 60 x 2/ number of poles the motor has.

Why the synchronous motor is always a salient pole machine ie why don't we use a cylindrical pole machine as a synchronous motor?

The speed of the machine is tied to the power supply frequency and the number of poles the machine has. It becomes impractical to make a round rotor machine with many poles, so machines that spin at low revolutions will typically be salient designs. A two or four pole machine could be round rotor designs.

Why the speed decreases when the poles increases in a motor?

because N=(120*f)/P where N= speed in rpm f= frequency in Hz P= no. of poles as the relations shows above it is cleare that speed of machine inversly proportional to no. of poles.. so as the poles increses, speed of the machine decreses

Single phase motor speed is determined by the?

Motor's number of poles.

You can determine quickly the effect of adding poles and zeros by?

Root locus

Does a magnet contains a large number of magnetic domains or poles?


What is parallel path in dc machine?

This describes the way the machine's armature conductors are connected relative to each other and to the number of poles. The two basic ways of connecting these conductors are called 'lap' and 'wave', but it gets more complicated, because these, in turn, can be connected 'simplex', 'duplex', 'triplex', etc.For lap windings, if there are p poles, then for:simplex: pduplex: 2ptriplex: 3petc.For wave windings, the number of parallel paths are:simplex: 1 x 2duplex: 2 x 2triplex: 3x 2etc.So, for a triplex lap winding machine with six poles, the number of parallel paths will be: 3p =3 x 6 = 18 parallel paths.

How can you change the poles of genrator?

The number of poles in a generator is determined by the engineer who designed it. The only way to change the number of poles is to completely re-manufacture the generator.

If you were given a magnet with unmarked poles how could you determine which pole was which?

You are dumb- a classmate.

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