A jack system will increase the potential energy of a heavy load by no more than 1000 J with a work input of 2000 J. The efficiency of the jack system is at most
A) 10%.
B) 20%.
C) 50%.
D) 80%.
E) not enough information
Answer: C
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What will be an ideal response?
Why was Voyager 2 an extremely efficient and productive probe?
What will be an ideal response?