A very inefficient device will waste most of its input energy. The efficiency of a device is the proportion of the energy supplied that is transferred in useful ways. The efficiency can be calculated ...
When an answer to a maths question is marked: full marks are given for the right answer (but it is very important to show your working so you can check your answer, and if you make a small slip, you ...
Some results have been hidden because they may be inaccessible to you
Show inaccessible results
Feedback