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mayankdevnani
 2 years ago
A steam engine has an efficiency of 20%.It is given an energy of 1000 cal.per minute.What is the actual work done by it in joule and in calories?
a) 100 cal,800 J
b) 200 cal,873 J
c)10 cal,80 J
d)100 cal,100 J
mayankdevnani
 2 years ago
A steam engine has an efficiency of 20%.It is given an energy of 1000 cal.per minute.What is the actual work done by it in joule and in calories? a) 100 cal,800 J b) 200 cal,873 J c)10 cal,80 J d)100 cal,100 J

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mayankdevnani
 2 years ago
Best ResponseYou've already chosen the best response.1@amistre64 @ParthKohli @hartnn @Callsito @Zarkon @Hero @.Sam. @estudier @ganeshie8 @ajprincess @Algebraic!

amistre64
 2 years ago
Best ResponseYou've already chosen the best response.0im not sure since we havent gone over this in my physics class yet, but i would say that 20% efficiency means that 20% of the 1000 cals are used; giving us 200 cals in the answer at least

mayankdevnani
 2 years ago
Best ResponseYou've already chosen the best response.1ofcourse @SheldonEinstein

SheldonEinstein
 2 years ago
Best ResponseYou've already chosen the best response.3;) OK so first of all what @amistre64 discussed in his previous comment is very imp. to do this quest., so @mayankdevnani do you know what does efficiency mean?

mayankdevnani
 2 years ago
Best ResponseYou've already chosen the best response.1ok @amistre64 then

mayankdevnani
 2 years ago
Best ResponseYou've already chosen the best response.1efficiency=winout/winin*100

mayankdevnani
 2 years ago
Best ResponseYou've already chosen the best response.1right @SheldonEinstein

SheldonEinstein
 2 years ago
Best ResponseYou've already chosen the best response.3Yeah or in simpler words it is : \(\large{\frac{\textbf{Output}}{\textbf{Input}}\times 100}\) it is 100%...

SheldonEinstein
 2 years ago
Best ResponseYou've already chosen the best response.3So, what we have is output/input * 100% = 20% , correct?

SheldonEinstein
 2 years ago
Best ResponseYou've already chosen the best response.3Ok so now, let me understand the second line of the quest. , is the output = 1000 calorie ?

mayankdevnani
 2 years ago
Best ResponseYou've already chosen the best response.1@SheldonEinstein then

SheldonEinstein
 2 years ago
Best ResponseYou've already chosen the best response.3I am getting diff. answer so I am checking it, sorry , it will require some patience.

SheldonEinstein
 2 years ago
Best ResponseYou've already chosen the best response.3Quest. is wrong

mayankdevnani
 2 years ago
Best ResponseYou've already chosen the best response.1why?? no it is right

SheldonEinstein
 2 years ago
Best ResponseYou've already chosen the best response.3Time is not given.. though if you take 1 minute it is 200 cal.

SheldonEinstein
 2 years ago
Best ResponseYou've already chosen the best response.3See , Power = 1000 cal/minute (given)

SheldonEinstein
 2 years ago
Best ResponseYou've already chosen the best response.3use this and you will get 200 cal. as answer.

mayankdevnani
 2 years ago
Best ResponseYou've already chosen the best response.1so what's the work done?

SheldonEinstein
 2 years ago
Best ResponseYou've already chosen the best response.3W = P * time if T = 1 second , W = P ... that's it , find P(output) .. (using efficiency = Ouput/Input *100%) in Cal. per minute , that will be your answer

SheldonEinstein
 2 years ago
Best ResponseYou've already chosen the best response.3200 cal.... = WORK DONE

mayankdevnani
 2 years ago
Best ResponseYou've already chosen the best response.1but the work done is in joule

mayankdevnani
 2 years ago
Best ResponseYou've already chosen the best response.1@ParthKohli @Preetha

SheldonEinstein
 2 years ago
Best ResponseYou've already chosen the best response.3Is my answer correct, i.e. 200 cal, 873 J ?

SheldonEinstein
 2 years ago
Best ResponseYou've already chosen the best response.3So where is the problem? ?? ? ?

mayankdevnani
 2 years ago
Best ResponseYou've already chosen the best response.1@SheldonEinstein how you got it 873J

SheldonEinstein
 2 years ago
Best ResponseYou've already chosen the best response.3I got 200 Cal, and it is in options, soo....

mayankdevnani
 2 years ago
Best ResponseYou've already chosen the best response.1can you help me @amriju

SheldonEinstein
 2 years ago
Best ResponseYou've already chosen the best response.3200 cal * 4.184 = 836 J (approx. ) not equal to 873 Joule , hence I think the options are wrong..

mayankdevnani
 2 years ago
Best ResponseYou've already chosen the best response.1no it was not wrong

amriju
 2 years ago
Best ResponseYou've already chosen the best response.0work done is 20 percnt of the energy given...thats efficiency....so per minute is 20percnt of 1000 cal...thats 200 cal...convert to joules

mayankdevnani
 2 years ago
Best ResponseYou've already chosen the best response.1so 1cal.=? j @amriju

amriju
 2 years ago
Best ResponseYou've already chosen the best response.04.2...approx..the correct is 4.187...

amriju
 2 years ago
Best ResponseYou've already chosen the best response.0thats how it is defined...both are units...and 1 cal is defined as 4.187 joules...

SheldonEinstein
 2 years ago
Best ResponseYou've already chosen the best response.3That is what I was saying @amriju

mayankdevnani
 2 years ago
Best ResponseYou've already chosen the best response.1in my solution book...the answer is as follows \[\frac{20}{100}=\frac{W}{1000}=200 calorie\] OR \[200\times4.37=873J\]

mayankdevnani
 2 years ago
Best ResponseYou've already chosen the best response.1is that right?? @amriju and @SheldonEinstein

SheldonEinstein
 2 years ago
Best ResponseYou've already chosen the best response.3That is wrong, 1 Cal. = 4.187 Joule NOT 4.37 joule...

mayankdevnani
 2 years ago
Best ResponseYou've already chosen the best response.1ok... thnx... @SheldonEinstein and @amriju

amriju
 2 years ago
Best ResponseYou've already chosen the best response.0u may jst check on wikipedia...and its seems that none of the options are correct...the closest being 200, 837

amistre64
 2 years ago
Best ResponseYou've already chosen the best response.0just for reference http://www.wolframalpha.com/input/?i=200+calorie+to+joule

amistre64
 2 years ago
Best ResponseYou've already chosen the best response.0if your options are truely: 200,873 then its most likely a typo and prolly meant to be read as 200,837
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