Calculating Watt Hours for a time interval less than 1 second

  • #1
pete94857
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TL;DR Summary
Is it OK to put less than 1 second into the equation ?
I use an online physics calculator a lot to help me for various reasons. When I input less than 1 second into a watt hour calculation it initially tells me it can not be a negative value although that does disappear and it does do the calculation.

Example power 10 w time 0.01 seconds 0.1 J watts hours.
 

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  • #2
pete94857 said:
Example power 10 w time 0.01 seconds 0.1 J watts hours.
I have no idea what a "J watts hours" is as a unit, and the number 0.1 looks incorrect to me.

Can you show us by hand how you would calculate 10W*0.01s with the results in Watt*Hours?
 
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  • #3
berkeman said:
I have no idea what a "J watts hours" is as a unit, and the number 0.1 looks incorrect to me.

Can you show us by hand how you would calculate 10W*0.01s with the results in Watt*Hours?
It is an ambiguous interface. The answer is in joules.
 
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  • #4
pete94857 said:
TL;DR Summary: Is it OK to put less than 1 second into the equation ?

I use an online physics calculator a lot to help me for various reasons. When I input less than 1 second into a watt hour calculation it initially tells me it can not be a negative value although that does disappear and it does do the calculation.

Example power 10 w time 0.01 seconds 0.1 J watts hours.
It doesn’t like zero, but greatery than zero seems ok. Watt-hours should be Energy.
 
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  • #5
berkeman said:
I have no idea what a "J watts hours" is as a unit, and the number 0.1 looks incorrect to me.

Can you show us by hand how you would calculate 10W*0.01s with the results in Watt*Hours?
Power x time = Energy. Power is the required energy to power something, time is the amount of time needed and energy is the energy needed to perform the task at that time. Or reverse E/t=w
 
  • #6
pete94857 said:
Power x time = Energy. Power is the required energy to power something, time is the amount of time needed and energy is the energy needed to perform the task at that time. Or reverse E/t=w
Well, that didn't really answer my question, but I'll show you how to do it since I don't think this is a schoolwork-related question.

So to calculate the Energy based on power and time and convert units from W*s to W*hr:

$$E = 10W ~0.01s ~ \frac{1hr}{3600s} = 27.8\mu Whr $$

Note how I converted from W*s (Joules) to W*hr by multiplying by "1" in this form: ##1=\frac{1hr}{3600s}## to get the right cancellations of units from the initial answer to what I wanted. :wink:
 
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