Thank you for your help.

Q20
Based on the narrow definition in the textbook, generally fuels consist of wood, coal, oil and natural gas. These fuels come from organisms that are once alive, meaning (c) is correct. I am wondering if nuclear energy is considered as fuel, meaning (c) is not true.

Q21
Statement(3) ---Is it correct?

Hi there,

As with many science questions, the answers are not as exact as say they are in math and as a result depend a lot on what is taught in the schools. My answers, therefore, try to take that into account while also being based on a greater understanding of the topic are.

Q 20)
There are two types of fuel including Conventional fuels and Alternative fuels. Typically the word fuel refers to conventional fuel which includes fossil fuels (coal, oil, gas) and nuclear fuel. Therefore, you are correct that nuclear is a fuel and thus C and D are not correct. Answer is 2.

A quick check also suggests this to be the case in that if, C was true than there would be no suitable answer to the question.

Q 21)
I differ in this answer with you. I believe the answer to be 2. Why? Solar energy refers to light energy and heat energy from the sun. In the question is states "only".

Why do I believe the answer to be 2? The energy, potential chemical, stored in the fossil fuels is originally from the plants. In cases, were fossil fuels come from animals, these also came from plants because animals eat plants or animals eat other animals who eat plants. As we know that plants get their energy from the sun through the process of photosynthesis.


Note:
From my experience, when dealing with multiple choice questions, it is rare that the correct answer would include the words "always", "only", "all". There are so many variations in this world for something to always (or never) occur. This is one tip my teachers gave me and thus far it has proven correct.

Hi Chris
I made a silly mistake for Q21. I am so focused on light from the Sun that I forgot about its heat.
Thank you for pointing that out. You may learn more about solar energy from this link.
http://www.eia.doe.gov/kids/energyfacts/...renewable/solar.html

Thanks for the link.

I think I will create a 'links' page whereby we can keep "trusted" relevant links.

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