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We know that Transformers allows us to step down or step up (Alternating Current) AC voltage!

Input voltage ${V_I}$ and output voltage ${V_O}$ is related to
primary winding ${N_P}$ and secondary winding ${N_S}$ using this following the ratio $\frac{V_I}{V_O}=\frac{N_P}{N_S}$

Also we know that if the transformer step downs the input voltage ${V_I}$ then this means that it increases the output current ${I_O}$ which equals k times input current ${I_I}$!

$K=\frac{V_I}{V_O}=\frac{I_O}{I_I}$

Let say that we have ${T_1}$ and ${T_2}$ two same big, heavy and high power transformers,
Which step downs input voltage $250 V AC$ to $50 V AC$ and if the maximum input current is $20A$ then the maximum output current will be $100A$
So $K=5$

Is it possible to connect both ${T_1}$ and ${T_2}$ transformers in series in order to get much higher current and much less output voltage?

We know that transformers are only working with $AC$ not $DC$!
If the first transformers $T_1$ step downs input voltage $250 V AC$ to $50 V AC$ then tell me is it possible to connect this input voltage $50V AC$ to another $T_2$ transformers?
What will be the result?
Will we get a $10V AC$ on a secondary winding on a $T_2$ transformer?
So input voltage will be $50V AC$ for $T_2$ transformer and it should step down this voltage 5 times lower! Right?

OK we get a $10V AC$ output voltage but...
Anyway what about current?
How much current will it allow me to use?
$T_1$ transformer had maximum output current $100A$ as 5 time higher then input current. Will $T_2$ transformer increase this $100A$ current 5 times higher again?
So will we get a $500A$ as maximum output current?

But we get this result after serial connection?
What will be if we will connect both $T_1$ and $T_2$ transformers in parallel?
So input voltage will be $250V AC$ for both transformers and $50V AC$ will be as output voltage for both transformers!
Input current will be $20A$ and output current will be $100A$ for both transformers!
but we are using two transformers in parallel, So we will have $2*20A =40A$ input current and $2*100A=200A$ output current! Right?

So both transformers connecting in parallel gives us $50V * 200A = 10'000W$ power.
But in series we got $10V * 500A = 5'000W$ power.
Is this true that transformers followed by each other in parallel gives us twice more power then followed in series?

Please answer my main important questions!

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The reason the cascaded (series) transformers deliver half the power of the paralleled ones is that in the case of the former, you are limiting the available power to that of a single transformer. The second one can only change the voltage and current available FROM the first - ie 5000W. In the parallel case, you are able to access double the power by virtue of TWO 5000W transformers combining their output to make 10kW.

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