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1

Your confusion is between two related concepts. Power dissipated in total = internal power + external power. If that is the power you are talking about, then an external short circuit will maximize the current and therefore maximize total power, $V\cdot I$. Power delivered to the load. That is the thing addressed by the maximum power transfer theorem, and ...


1

For a force to do work, it must act upon an object as that object moves some distance (with a component along or opposed to the direction of that force). Holding an object stationary, but carrying the strength of a given force, adds no more work done. Because of this, we say that $$W=\int_C\vec{F}\cdot d\vec{r}$$ where C is the curve in space along which ...


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This is because $P(t)$ as stated is the instantaneous power as a function of time and $W =\mathbf F\Delta \mathbf x$ holds only for constant forces. More generally, recall that a definition of work is the integral: $$W = \int_C\mathbf F(x)\mathrm d\mathbf x$$ Where $C = C(x,t)$ is some curve in space/time. Expressing in terms of time gives: $$W = ...


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I actually did this for a battery control driver for a tablet. The only way I found to do it was to take manufacturers charge/discharge curves as functions of temperature and number of cycles and encode them by hand in a lookup table. This does assume that the manufacturer has enough data, the data is accurate, and is willing to supply it.


0

Power factor means ratio of power consumed by LCR circuit to power consumed by resistive circuit. If Power factor is 0, it means No power is consumed by LCR circuit, although power supply is given.It acts like open circuit. When power factor is 1, it means all power supplied by source is being consumed. This is called resonance condition. Power factor ...


0

Ultraviolet would be the best the short wavelengths carry a lot of energy.


3

Hitting the air twice as fast takes four times as much energy ($E = {1\over 2} m v^2$). So there's an extra factor of two. To expand a little; you're fighting drag ($F_d$) in a rowing machine and drag increases as the square of velocity. ($F_d \propto v^2)$. Now, $Energy = force \times distance$ and $Power = {energy \over time}$ so $Power = force \times ...


3

If we indeed suppose that such an exotic material did indeed exist, then we just have to consider the flux of solar neutrinos from proton-proton fusion. This is about $10^{11} cm^{-2}s^{-1}$ at about 0.4 Mev each. So a one-metre square sheet of annixxite, would generate, in Watts: $$ {1\over2} \times 10^{11} \times 10^4 \times (0.4 \times 10^6) \times ...


-1

Looking for something else accidentally found your conversation Probably is useless after 3 years but let me make a comment Nothing new, but putting it in on other way Keeping the current fix in the formula Q=I2Rt, shows that the energy amount converted to heat in a resistor is proportional to the resistance. This is because in order to keep the current ...



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