The ultimate source of energy is

Options

A. wood
B. wind
C. water
D. sun

Answer

**Step-by-Step Solution:**

1. **Identify the Question**: The question asks for the ultimate source of energy.

2. **Understanding the Concept**: The ultimate source of energy refers to the origin from which all other forms of energy derive.

3. **Recognize the Role of the Sun**: The Sun is identified as the ultimate source of energy. It is a star that emits light and heat, which are essential for life on Earth.

4. **Explain the Process of Energy Generation in the Sun**: The Sun generates energy through nuclear fusion, where hydrogen atoms combine to form helium, releasing a massive amount of energy in the process.

5. **Energy Transfer to Earth**: The energy produced in the Sun travels through space and reaches Earth in about 8 minutes, covering a distance of approximately 93 million miles.

6. **Forms of Energy Derived from the Sun**: Almost all forms of energy used on Earth, such as chemical energy (from photosynthesis), wind energy (from temperature differences caused by the Sun), and hydroelectric energy (from the water cycle driven by solar heat), originate from the Sun.

7. **Conservation of Energy**: According to the law of conservation of energy, energy cannot be created or destroyed but can change forms. The energy from the Sun transforms into various other forms that we utilize.

8. **Conclusion**: Therefore, the ultimate source of energy is the Sun, as it is the origin of nearly all energy forms on Earth.

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