How do to solve this sankey diagram?

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1 Answer
May 3, 2018

The correct answer is #option (A)#

Explanation:

The total energy (by counting the squares) is

#E_t=3+1+1+5=10u#

The energy lost is

#E_l=7 u#

The useful energy is

#E_u=3u#

The efficiency is

#eta=E_u/E_t=3/10=0.3#

The correct answer is #option (A)#