In real machines, as opposed to ideal machines, there is always friction that reduces the efficiency of the machine. Lubricants like oil can be used to reduce friction and improve efficiency.
nothing has 100% efficiency.
No. Nothing mechanical can ever have a 100% efficiency by any physical evaluation.
why is the efficiency of a calorimeter less than 100%
If a machine has 100 percent efficiency, the output work = the input work. That's actually basically what the efficiency of a machine is - output work / input work * 100.
The laws of thermodynamics imply that there will always be some loss of efficiency.
"Unity"
100% efficiency would mean that the machine is able to transform energy from one form into another without any loss of energy from the system in the process. For it to have greater than 100% efficiency, it would have to somehow generate additional energy, not contained in the system, in the process, and this is not possible.
(work out/work in) x 100
Because there is always going to be friction, the efficiency of any machine will always be less then 100 percent.
Percent efficiency is a measure of how well a system or process converts input resources into output results. It is calculated by dividing the actual output by the theoretical maximum output, then multiplying by 100 to express it as a percentage. A higher percent efficiency indicates a more effective use of resources in achieving desired outcomes.
Efficiency % = (Output/Input) x 100
The formula for the percent efficiency of a pulley is (output work/input work) x 100%. It compares the output work (work done by the pulley) to the input work (work done on the pulley) to determine how efficient the pulley system is in transferring energy.