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41 votes
41 votes
A physicist does 100 joules of work on a simple machine that raise a box of bioks through a heigjt of 0.2metres. if the efficiency of the machine is 60%, how much work is converted to thermal energy?​

User Aerojun
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1 Answer

19 votes
19 votes

Answer:

the work converted to thermal energy is 40 J.

Step-by-step explanation:

Given;

work done by the physicist,w = 100 J

height through which the book is raised, h = 0.2 m

efficiency of machine = 60% = 0.6

The useful work done by the machine is calculated as;

useful work = 0.6 x 100 = 60 J

The wasted energy = 100 J - 60 J

The wasted energy = 40 J

The wasted energy by the machine is possibly converted to thermal energy by the frictional part of the machine.

Therefore, the work converted to thermal energy is 40 J.

User Shay Shmeltzer
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