Answer:
Explanation:
From the given information:
The speed of a synchronous motor in relation to its frequency can be represented with the formula:

where,
the electrical frequency
is measured in Hz
the number of poles = P
For us to estimate the number of poles to have 50 Hz - 60 Hz Power, then we need to relate the frequencies of the above equation.
i.e

Thus, we can conclude that 10 poles synchronous motor is attached with 12 poles synchronous generator in order to convert 50 Hz to 60 Hz power.
Answer:
Inductive reactance is 125.7 Ω
Explanation:
It is given that,
Inductance, 
Voltage source, V = 15 volt
Frequency, f = 400 Hz
The inductive reactance of the circuit is equivalent to the impedance. It opposes the flow of electric current throughout the circuit. It is given by :




So, the inductive reactance is 125.7 Ω. Hence, this is the required solution.
Period = (1) / (frequency)
Period = (1) / (200 per second) = 0.005 second = 5 milliseconds
You'll hear that force called different things in different places. It
may be called "electromotive force", "EMF", "potential difference",
or "voltage".
It's just a matter of somehow causing the two ends of the wire
to have different electrical potential. When that happens, the
free electrons in the copper suddenly have a burning desire to
travel ... away from the end that's more negative, toward the end
that's more positive, and THAT's an "electric current".
Metamorphic rock this possess often occurs in the mantle