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3 years ago

Why is using fossil fuels considered unsustainable?

Physics

2 answers:

Elena L [17]3 years ago

8 0

Answer:

Fossil Fuel is limited it is like coal there is a limit and it won't last forever. This also contributes that it is not safe for the environment as well as the safety and health of people. This is similar to when there are many factories around an area there is going to be a high percentage of respiratory diseases such as asthma.

ikadub [295]3 years ago

3 0

Answer:

Fossil fuels take millions of years to replenish

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Since force is mass*acceleration,

F = 70kg * 9.8 m/s

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The resistance of a conductor is 10 ohm at 50 degree celsius and 15 ohm at 100 degree celsius. Calculate its resistance at 0 deg

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A cable with mass 0.5 kilograms per meter (kg/m) is used to lift 150 kg of coal up a mine shaft 50 meters deep. Set up the integ

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4 years ago

The power of a lens is defined as the reciprocal of its focal length: P = 1/f. (Thus power is measured in inverse meters, called

Len [333]

Answer:

This the power of combination is given by

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Explanation:

Let 'F' be the focal length of the combination of the two lenses and the focal length's of individual lenses be $f_{1},f_{2}$

We know that focal length is the position of image when object is placed at infinity

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$\frac{1}{f_{1}}=\frac{1}{u}+\frac{1}{v}$

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$\frac{1}{f_{1}}=\frac{1}{\infty }+\frac{1}{v}\\\\\Rightarrow \frac{1}{f}=0+\frac{1}{v}\\\\\therefore v=+f_{1}$

Now this position of image formed by the first lens act's as object for the second lens, thus we have

$\frac{1}{f_{2}}=\frac{1}{-(d-f_{1})}+\frac{1}{v}\\\\\Rightarrow \frac{1}{f_{2}}+\frac{1}{d-f_{1}}=\frac{1}{v}\\\\\therefore \frac{1}{v}=\frac{(d-f_{1})+f_{2}}{f_{2}(d-f_{1})}\\\\=\frac{1}{v}=\frac{d+f_{2}-f_{1}}{f_{2}(d-f_{1})}\\\\\therefore v_{f}=\frac{f_{2}(d-f_{1})}{d+f_{2}-f_{1}}$

Since image of an object placed at infinity will be formed at $v_{f}=\frac{f_{2}(d-f_{1})}{d+f_{2}-f_{1}}$ thus the focal length of the combination of the 2 thin lenses will be $F=\frac{f_{2}(d-f_{1})}{d+f_{2}-f_{1}}$

This the power of combination is given by

$P_{combination}=\frac{1}{F}=\frac{d+f_{2}-f_{1}}{f_{2}(d-f_{1})}$

(For the sake of question we assume lenses to be convex although the same procedure is valid for all other lenses)

5 0

4 years ago