(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

I'm trying to calulate the efficency of a small hydrogen fuell cell that I built. I have all of the measurements, but I'm not coming up with a resonable effiency.

2. Relevant equations

[tex]\frac{P OUT}{P IN}[/tex]x 100

The power to electrolyze the water is the P IN.

3.25 W =2.5 V x .00021 Amps (.21 mA)

We measured the electrical power out finding the voltage and amperage.

P OUT = V x I

2.01 x 10^-4 W=.96 V x .00021 AMPS (.21 mA)

I caulcate the force to be 1.421 N

Then I take the electrical P Out and use it as the P IN for the car

the P IN for the car is the electrical P Out

and the P Out for the car is F x V

To find the % efficiency:

[tex]\frac{p Out of the Car}{P in Car}[/tex] x 100

The avg velocity is .0198 m/s

3. The attempt at a solution

I'm coming up with an unreasonable calculation

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# Homework Help: Calculating the efficency of a hydrogen fuel cell

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