A machine which is 75 % efficient uses 12 J of energy lifting up a 1 kg mass through a certain distance . The mass is then allowed to fall through that distance. What will be its velocity at end of fall:

A machine which is 75 % efficient uses 12 J of energy lifting up a 1 k

1.	A machine which is 75 % efficient uses 12 J of energy lifting up a 1 kg mass through a certain distance . The mass is then allowed to fall through that distance. What will be its velocity at end of fall:
Answer» `sqrt(24) m//s` `sqrt(32) m//s` `sqrt(18) m//s` `sqrt(19) m//s` Solution :WORK DONE =`(75)/(100)xx12=9 J`. `1/2mv^(2)=9impliesv=sqrt((2xx9)/(1))=sqrt(18)ms^(-1)`.

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A machine which is 75 % efficient uses 12 J of energy lifting up a 1 kg mass through a certain distance . The mass is then allowed to fall through that distance. What will be its velocity at end of fall:

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