Difference between the power dissipation and power

[iVenki]

I confuse the terms "power" and "power dissipation".

I know that the power dissipated through a resistor is I^2 R or VI. But what is the power of the dc supply?

What is the formula for both of them?

Both seem to have the same formula.(ie VI)

Then what is the difference between them?

---------- Post added at 16:30 ---------- Previous post was at 15:30 ----------

If you say the formula for power supply is also VI then I have one question.

Consider that I have two batteries. The power of a dc supply is always a constant. It means that when the current increases then Voltage should increase but total voltage always remains same (For example consider two circuits having different resistances( and hence different currents) will have have the same potential when each of them is connected to a battery).

I can't understand this. Please help me .
Thanks in advance.

 

[hussain_kiet]

since both of them are power therefore the formula has to be same...
the power of a DC supply is basically the power a DC supply can deliver, i.e the nominal voltage multiplied by max current of supply...
while power dissipation is the power dissipated by the component eg two equal resistors are connected across the terminals of the DC supply then each of them will dissipate exactly half of the power supplied by the DC supply..
and in case only one resistor is connected across the DC supply then all of the power supplied will be dissipate by the resistor i.e the DC supply Power = Power Dissipated by resistor..

hope this helps...

---------- Post added at 12:08 ---------- Previous post was at 12:01 ----------

If you say the formula for power supply is also VI then I have one question.

Consider that I have two batteries. The power of a dc supply is always a constant. It means that when the current increases then Voltage should increase but total voltage always remains same (For example consider two circuits having different resistances( and hence different currents) will have have the same potential when each of them is connected to a battery).

I can't understand this. Please help me .
Thanks in advance.

yes both circuits will have different currents and same voltage hence different powers since it is upto the load that how much power it draws from the supply i.e how much current at a fixed voltage...
yes P=IV but you should also consider V= IR...

 

[Kral]

Think of power dissipation as the power "consumed" by a load. A resistive load converts the power to heat over time. An ideal power supply delivers current at a certain voltage, but it does not dissipate any power