Answer:
1.04%
Explanation:
Given that,
The power of drill = 3.5 kW = 3500 W
Transferred kinetic energy = 5000 kJ during 15 seconds of use.
We need to find the percentage efficiency of the drill. It can be given by :
[tex]\eta=\dfrac{P_o}{P_i}\times 100[/tex]
Where
Po and Pi are output and input powers.
[tex]P_o=\dfrac{5000\times 10^3}{15}\\\\=3.34\times 10^5\ W[/tex]
So,
[tex]\eta=\dfrac{3500}{3.34\times10^{5}}\times100\\\\=1.04\%[/tex]
So, the percentage efficiency of the drill is 1.04%.
