228k views
0 votes
Suppose you left your lawn mower out all winter, and it is very rusty. Of your 250,000J of work, only 100,000J go towards cutting the lawn. What is the efficiency of the lawn mower now?

A 40%
B 0.4%
C 0.04%
D 4%

REMINDER: PLEASE SHOW YOUR WORK!!!

User Klox
by
6.1k points

1 Answer

5 votes
Efficiency =

(useful work you get out of it) / (work you put into it)

= (100,000 J) / (250,000 J)

= 0.4 = 40% (choice-A)


User Sriram Sitharaman
by
6.0k points