Answer:
Efficiency of the lever is 80 %.
Explanation:
Given that, if the work put into a lever is 25.0 joules and the work done by the lever is 20.0 joules. We need to find the efficiency of the lever. The mathematical expression for the efficiency is given by :
[tex]\eta=\dfrac{W_o}{W_i}\times 100[/tex]
Where
[tex]W_o\ and\ W_i[/tex] are output and input work respectively.
[tex]\eta=\dfrac{20}{25}\times 100[/tex]
[tex]\eta=80\%[/tex]
So, the efficiency of the lever is 80 %. Hence, this is the required solution.
