Need confirmation- Energy and PEgrav

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To raise a 0.9 kg mass 1.5 km into the air, 13,243.5 Joules of energy is required. Given that beer contains approximately 1.8 million Joules per kilogram, the calculation shows that only about 7.36 grams of beer is needed to provide this energy. The initial concern about the low amount was clarified by comparing the energy needed to the energy provided by beer. The discussion confirms that the calculations are correct and the amount of beer required is indeed minimal. Overall, the energy content of beer can efficiently meet the gravitational potential energy requirement for this scenario.
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The energy content of beer is about 1.8e6 J/kg. If that energy could be turned completely into gravitational PE, how much beer would we need to raise a 0.9 kg mass 1.5 km into the air?

What i did for this, was just used the equation PEgrav=mg*delta H.

so .9kg*9.81m/s^2*1500m =13243.5 kgm^2/s^2.

So i set that =1.8e6J/kg, and divided 13243.5 by 1.8e6, giving me .0073575kg.

So, i need 7.3575 grams of beer correct?

It just seems really low to me so just looking for confirmation.

Thanks
 
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Not at all. You need 13243.5 Joules of energy, and there is what? 18000000 Joules per kilogram in beer? Looking at the numbers side by side

13243.5 - Needed
1800000 - Provided per kg
1800.0 - Provided per gram
======================
 
oh alright, thanks :D

I was right, just hadn't thought about it like that.
 

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