Answer:
The machines efficiency is 80% .
Step-by-step explanation:
Formula
[tex]Efficiency = \frac{W_{out}\times 100}{W_{in}}[/tex]
Where [tex]W_{out}[/tex] represented the output work .
[tex]W_{in}[/tex] represented the input work .
As given
If a machine input of 5,000 joules of work to put out 4,000 joules of work .
Input work = 5000 joules
Output work = 4000 joules
Putting the values in the formula
[tex]Efficiency = \frac{4000\times 100}{5000}[/tex]
[tex]Efficiency = \frac{400000}{5000}[/tex]
Efficiency = 80%
Therefore the machines efficiency is 80% .
