I.i = j.j = 1
i.j = j.i = 0
(-2i - 5j)(i -4j)
= (-2i).i + (-2i).(-4j) + (-5j).i + (-5j).(-4j)
= -2 + 0 + 0 + 20 = 18
<h3>
Answer:</h3>
539.56 Joules
<h3>
Explanation:</h3>
- Efficiency of a machine is the ratio of work output to work input expressed as a percentage.
- Efficiency = (work output/work input) × 100%
- Efficiency of a machine is not 100% because so energy is lost due to friction of the moving parts and also as heat.
In this case;
Efficiency = 94%
Work input = 574 Joules
Therefore, Assuming work output is x
94% = (x/574 J) × 100%
0.94 = (x/574 J)
<h3>x = 539.56 J</h3>
Thus, you get work of 539.56 J from the machine
2.3 grams of wood has the same energy as 1g of oil.
The majority of wood and wood waste used as fuel in the United States is used by industry. Manufacturers of paper and wood products are the biggest industrial users. They produce steam and electricity from waste from paper and lumber mills, which saves money by lowering the number of other fuels and electricity they need to buy to run their facilities.
There are numerous power plants that primarily burn wood to produce electricity in the electric power sector, and some coal-burning power plants burn wood chips along with coal to cut down on sulfur dioxide emissions. The primary purpose of wood consumption in the business sector is heating.
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