Re: TI-H: 92 battery pack expander
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Re: TI-H: 92 battery pack expander
>1 Watt is approximately 0.2388 calories per second.
>A dietary calorie is equaly to 1000 calories. So, if you
>were to expend 200 dietary calories per hour during exersize,
>you would be expending about 230 W, about .3 horsepower :)
>
> 200 dCal 1000 Cal
> -------- * --------
> hr dCal 4.1868 Cal
> --------------------- * ---------- = 233 Watts
> 3600 sec Watt
> --------
> hr
Careful with your units there... If you're talking about total energy
expended, you must multiply watts by time, hence the reason why your
electric bill is specified in watt-hours. If you're talking about
your instantaneous energy expenditure, then you can leave the unit as
watts.
>Power can be released in the form of heat when an electrical
>current flows through a resistance, according to the formula
>P = VI^2 (Unless I misremember), where P is Watts, V is volts,
>and I is Amps.
P = V*I
P = (I^2)*R
P = (V^2)/R
Most of the power is not released as heat. Power is consumed because
it takes energy to move electrons at a specified rate through a
specified resistance. Heat is simply an unwanted byproduct and
consumes a comparatively small amount of energy in most systems.
>200mA (.2 Amps) at 5 volts flowing through a resistance will
>expend .2 Watts. Since the voltage and current are known,
>the resistance can be calculated to be about 25 Ohms.
V*I = 0.2 * 5 = 1 watt
-Mel
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