power and efficiency

Question 1

what is power

Answer 1

is the rate of doing work

Question 2

whats the formula for calculating power

Answer 2

power = w/t

Question 3

what is power measured in

Answer 3

watts or j/s

Question 4

what is the formula for efficiency

Answer 4

efficiency = usefull energy output/total energy output

Question 5

what is efficiency

Answer 5

is the ratio of the useful output work to the total energy input