EFFICIENT ENGINES

ya its not possible to attain 100% efficient engine practically ...but theoritically its possible with carnots engine ...ifu attended the class in tht calss u might have herd abt tht..but for practical application new cocepts are arriving like the green engine six strokie engine etc...so in near future u may a expect a n above 50 engines

A day might come that it will become a reality.We cant say that anything is imposible.I even saw an Engineering student made such a machine for experiment purpose in one Exhibition.That time I was too young to grsp it.I also know that student got first prize for his project.Lets hope for that day when such machine with 100% efficiency.