The diagrams below show a structure that is used to generate electricity from wave power.

Essay topics:

The diagrams below show a structure that is used to generate electricity from wave power.

The diagrams graphically demonstrate how electrical energy is produced in two steps by taking advantage of the wave power.

Turning to the diagram A, on the ocean floor a chamber is constructed, and the chamber is situated beside the cliff or the sea wall. Whenever the wave advances, the chamber guides the wave towards a vertical column in which a turbine is located. Thence, the movement of the water flow increases the pressure of the air at the bottom of the column. In turn, an air flow takes shape inside the column, and this flow rotates the turbine on counterclockwise. Afterwards, the axial rotation of the turbine produces electricity.

Looking at the diagram B, the energy reduction of the wave brings about retreating the water flow and the wave returns back into the inlet of the chamber. This phenomenon lessens the air pressure at the bottom of the column. Therefore, the air inside the column is sucked out and then a new air flow, which revolves the turbine on anticlockwise, commences to move down. As a result the electricity is generated.

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the wave returns back into the inlet of the chamber.
the wave returns the inlet of the chamber.

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Attribute Value Ideal
Score: 6.5 out of 9
Category: Good Excellent
No. of Grammatical Errors: 1 2
No. of Spelling Errors: 0 2
No. of Sentences: 10 10
No. of Words: 181 200
No. of Characters: 856 1000
No. of Different Words: 94 100
Fourth Root of Number of Words: 3.668 4.0
Average Word Length: 4.729 4.6
Word Length SD: 2.706 2.4
No. of Words greater than 5 chars: 64 60
No. of Words greater than 6 chars: 46 50
No. of Words greater than 7 chars: 29 40
No. of Words greater than 8 chars: 17 20
Use of Passive Voice (%): 0 0
Avg. Sentence Length: 18.1 21.0
Sentence Length SD: 6.625 7.5
Use of Discourse Markers (%): 0.2 0.12
Sentence-Text Coherence: 0.424 0.35
Sentence-Para Coherence: 0.559 0.50
Sentence-Sentence Coherence: 0.096 0.07
Number of Paragraphs: 3 4