0
votes
0answers
105 views

What would the graph between P (power) and i (current) look like if the graph between V (potential difference) and i is parabolic?

The answer is same... That us the graph between P and I will also be a parabola.... Similar to the graph between V and I. But how? Can anyone explain through mathematical approach ? I used ...
1
vote
3answers
56 views

Electric Power $P$

In my textbook there are 2 formulas for electric power: $$\begin{array}{cccr} P &=& E/t &\hspace{10pt} (1) \\ P &=& VI. &\hspace{10pt} (2) \end{array}$$ What is the ...
-1
votes
1answer
24 views

Computing power based on weighted averages [closed]

I'm struggling to understand the reason why I'm getting different results with two apparently similar ways to compute the power consumption (over multiple time intervals) of an electrical circuit. ...
0
votes
1answer
63 views

Is powered delivered to an Incandescent light bulb changing with time? [duplicate]

Initially, when the current starts flowing the temperature of the filament is less and thus resistance is less. So, more current flows through the bulb and the power delivered to the bulb is more. As, ...
-1
votes
3answers
206 views

Why do high current conductors heat up a lot more than high voltage conductors?

120 volts x 20 amps = 2,400 Watts However, if I increased the voltage and lowered the current, you can also use a smaller wire size (more inexpensive), also have less heat and achieve the same watt ...
1
vote
1answer
691 views

Power dissipated on internal resistance of short-circuited voltage source

Suppose we have a voltage source with an EMF of $\mathcal{E}$ and an internal resistance $R$. If we connect to it a perfect wire with zero resistance, we get a short circuit. The value of the current ...
1
vote
1answer
287 views

Electric power for current density

The electric power produced by a current $I\in\mathbb{R}^+$ and a voltage $V\in\mathbb{R}^+$ is $$ P = IV. $$ Now the current is given as an (alternating) current density ...
6
votes
5answers
711 views

Difference between ways of transmitting power

There are two ways to transmit the same amount of power, 1 amp at 1 million volts or 1 million amps at 1 volt. Conceptually what is the difference? How can I think about it conceptually? I would ...
0
votes
2answers
124 views

Electric power transmission

If we want to transmit electic current for a long distance, we must minimize a heat that releases because of the resistanse. We cannot make a cable wide because it is expensive and it will be massive. ...
0
votes
2answers
7k views

Confusion about P=VI and V=IR

If we look at $P=VI$, we see that if the current doubles then the potential difference is halved but this doesn't seem to make sense according to $V=IR$. If we look at that equation, since the ...
1
vote
2answers
2k views

Does the 'mAh' rating of a battery have something to do with its power?

I'm curious about the 'mAh' of a battery: how can this impact the power of the battery? I've done some research on the internet, and most of the articles I found explain about the 'amount of charge ...
1
vote
2answers
412 views

Calculate power $P=V \times I$

I have an adapter which mentions like this... Input: 100-240V~1.8A 50-60hZ So how much power does it really consume? I just knew ...
1
vote
1answer
74 views

is it possible to gain from charging cold battery

Is it possible to get higher load of energy into a battery if you charge it when its cold eg. +9C? the battery is emptier, but does it let the power in? Is it safe?
3
votes
1answer
228 views

Lifetime of battery

If I directly connect two terminals of 3V battery (negative to positive) using copper wire, would it lose all its charge faster compared to another 3V battery that is used to lighten a 1.5V bulb?
1
vote
5answers
344 views

How do electrical devices suck electricity?

If the electric potential is 220V and some device needs 1500watts then how does it suck exactly that amount of electrical energy from outlet?