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View Full Version : conservation of energy false?


invisiblebrain
May 3rd, 2004, 1:43 AM
im a medical guy ,so dont bash me if im wrong,just correct me.

if a train is coneected to 2 engines one of which has speed of 40 and other 60,and if both are started simultaneously what will be the speed of the train?

will it be 60
above 60
below 60 and above 40
1>it is 60 because 60 overrides 40.(my presumed ans)
2>abvove 60 because some load will be shared by 40 which helps to pull it
3>previosly a 40 engine was attached and now a >40 is attached ,so the speed will be above 40 but below 60

well i thought that 60 was right so where does the energy used up by 60 go?

timo
May 3rd, 2004, 8:29 AM
Engines donīt have speeds, only powers. The rest of your post thus becomes useless due to improper definition of the problem (no offense, itīs just impossible to scientifically correctly answer the question without further assumptions). Nevertheless, any additional condition you could give (which must make sense, of course) will lead to conservation of energy (most likely due to friction of the wheels that rotate to fast or to slow on the tracks).