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igor_vitrenko [27]
3 years ago
8

a machine has an efficiency of 70 percent, how much work does the machine do when 20000 j of work is done on it a. 14000 b. 2060

0 c. 1400000 or c. 2860000
Physics
1 answer:
Vlad [161]3 years ago
4 0

Answer:

a. 14000

Explanation:

Given parameters:

Efficiency of the machine  = 70%

Work done on machine  = 20000J

Unknown:

Work done by machine = ?

Solution:

 Efficiency of a machine is determined by;

  Efficiency  = \frac{Work done by machine}{Work done on machine}  x 100  

   70  = \frac{Work done by machine}{20000} x 100

   

   70  = \frac{work done by machine}{200}  

 Work done by machine  = 70 x 200 = 14000J

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