What is a "real life scenario"?
Now-days we have virtual reality etc.
Electric power is indeed P=v*i.( voltage*current)
Changing power will happen if either v or i or both are changed.
We can also say P=v*v/r=i*i*r.
What is r(resistance)?
r=v/i
That may be split further into static-resistance, i.e. fixed,not changing .
and dynamic-resistance ,i.e changing in time and dependent on circuit conditions like voltage/current/temperature etc.
There is the strange case of negative resistance as well i.e. an element that produces power.
To not confuse you too much we should stick with the static resistance ideal part.
It would be an ideal resistor i.e it's resistance is not depended on anything .
Let's connect it to an ideal voltage source,it has the property of keeping a fixed voltage level(which we can set up to be anything we like i.e like a bench power supply).
In this case,
if we change the voltage,we can say that it is the factor that changes the "working condition" and the power of the circuit.
The current will change as well by v/r.
Example if r=1 ohm changing the voltage from 1v to 2v will change the current from 1A to 2A and the power from 1W to 4W.
BTW'
The electric power grid and a car battery are very close to being called ideal voltage sources.
Now let's connect an ideal current source,it has the property of keeping a fixed current level(which we can set up to be anything we like).
This source isn't very common in everyday life,but exist in labs etc.
In this case,
if we change the current,we can say that it is the factor that changes the "working condition" and the power of the circuit.
The voltage will change as well by i*r.
Example if r=1 ohm changing the current from 1A to 2A will change the voltage from 1V to 2V and the power from 1W to 4W.
Hope this helps.
Now-days we have virtual reality etc.
Electric power is indeed P=v*i.( voltage*current)
Changing power will happen if either v or i or both are changed.
We can also say P=v*v/r=i*i*r.
What is r(resistance)?
r=v/i
That may be split further into static-resistance, i.e. fixed,not changing .
and dynamic-resistance ,i.e changing in time and dependent on circuit conditions like voltage/current/temperature etc.
There is the strange case of negative resistance as well i.e. an element that produces power.
To not confuse you too much we should stick with the static resistance ideal part.
It would be an ideal resistor i.e it's resistance is not depended on anything .
Let's connect it to an ideal voltage source,it has the property of keeping a fixed voltage level(which we can set up to be anything we like i.e like a bench power supply).
In this case,
if we change the voltage,we can say that it is the factor that changes the "working condition" and the power of the circuit.
The current will change as well by v/r.
Example if r=1 ohm changing the voltage from 1v to 2v will change the current from 1A to 2A and the power from 1W to 4W.
BTW'
The electric power grid and a car battery are very close to being called ideal voltage sources.
Now let's connect an ideal current source,it has the property of keeping a fixed current level(which we can set up to be anything we like).
This source isn't very common in everyday life,but exist in labs etc.
In this case,
if we change the current,we can say that it is the factor that changes the "working condition" and the power of the circuit.
The voltage will change as well by i*r.
Example if r=1 ohm changing the current from 1A to 2A will change the voltage from 1V to 2V and the power from 1W to 4W.
Hope this helps.