Difference between POWER and ENERGY

[darock]

difference between power and energy

I am always confused with the difference between power and energy of a signal as they are used interchangeably in research papers.

We know the difference between energy and power signals...power signals have infinite energy but finite power..

But my question is more in terms of communication theory or to some extent information theory...

The fact that we use baseband represenation adds more confusion... and how does amplitude connect these two quantities..

I will be grateful if someone enlightens the fundamentals behind this question.

thanks

 

[darock]

what is difference between power and energy

what is the funda behind the battery power..
the AA battery which we commonly use..says 1W etc...how is it defined

 

[scheik]

difference between energy and power signals

Power is simply VI
And Energy is how much power u are using for a particular time

 

[IanP]

difference between power and energy signals

Some companies, such as SONY, for example, have introduced Wh, but that has been done to confuse unaware users ..
But, I have never heard of 1W AA battery ..
Regards,
IanP

https://www.camerahacker.com/Definitions/Battery_Capacity_Conversion.shtml

 

[Manoj Mulajkar]

difference between energy and power signal

Power is VI assuming unity PF (Power factor) measured by unit Watt.

energy is like power with time as like KWH (Kilowatt/ Hr)

 

[III]

what is the difference between power and energy

Simply put Power is the capability of doing work or the capacaty of a system to do something. While energy is what is wasisted or gaind by doing somthing.
Power is static and Energy dinamic This is as clear as it can get with out Higher Math.

 

[darock]

difference between energy signal and power signal

then why does battery die out after some time...so it has only finite energy...

then why do we say a communication system has some power P? does it mean it has infinite enrgy capacity?

 

[III]

what is the difference between energy and power

Well batteries die out because the electrolyte corrodes .
A communication system that has power P uses Energy E=PxT [T being time] so in infinite time it does use (convert) infinite Energy . A Passive system can not have energy.
And we all know the fundamental low of everything: Energy is neither created or lost it simply changes from one form to another

 

[jallem]

difference between power signal and energy signal

then why does battery die out after some time...so it has only finite energy...

then why do we say a communication system has some power P? does it mean it has infinite enrgy capacity?

Infinite energy in communications systems only means you do not care
about time. En reality is like saying power is energy per units of time, so is
normalized. So power is the normalization of energy in units of time.

 

[hemlock]

difference between energy power

noob!!
how about you wiki or google before you post a question
https://en.wikipedia.org/wiki/Energy
https://en.wikipedia.org/wiki/Power_(physics)

 

[III]

difference power energy

Power is the first differential of energy so in realaty we'ld have P(t) = dE(t)/dt;
And the energy in a system observed in the time period between t1 and t would be the integral of the power in that system E(t)=∫P(t)dt.
This would equal multiplication only when the Power of the system wore constant.
If the Energy of the system was constant there would be no work done with in that system so it's power would be zero

 

[pico]

diff b/w signal power and signal energy

Power = Energy per unit of time.

 

[Jaideep Singh]

Re: difference between power and energy

sorry if i am replying to late to this post...
i have read all junk here...,, An energy of a signal refers to integration of square of the signal over a period from - inf to +inf ,, at the same time if we say the same signal exists for some finite limits, then the same square of signal integrated between that period would give power of the signal and would be a power signal. physically a signal that lasts for a long interval of time( tends to inf) is an energy signal and one which has limits definable easily is a power signal..

why do we need to create all this thing? energy and power signal?
let us consider a signal v(t). Now let us be in a condition that we need to tell someone, how our signal is..? big small, wide, short etc.... we cud do this by telling him in terms of amplitude phase etc but for how much time...,? what if it is a varying signal. so to make quantisation simple we take energy into consideration. square of v(t) ensures as well that all the negative part of the signal is considered positive. so we could easily tell, how much energy is there in our signal (ofcourse integrating b/w -inf to +inf) and same if it is a small signal,, may be a small pulse , we could tell power of it..(integrated b/w -t to +t) ., physically both terms do not have any DIFFERENCE. DONT CONFUSE IT WITH ENERGY=POWER/T . it is a communication analogy.