Hydrogen gas is supplied to the anode of the fuel cell. The anode is coated with platinum, which acts as a catalyst to break down the hydrogen into protons and electrons. If a circuit is connected between the anode and cathode then the electrons can travel through the circuit and provide power to any load that is connected as part of the circuit. Hydrogen does not occur naturally in the environment, hydrogen fuel must be derived from other substances that contain hydrogen such asmethanol, gasoline, natural gas, and water. Most hydrogen that is produced today comes from natural gas. If hydrogen is made from water the only byproduct is pure water. If fossil fuels are used as the original source of hydrogen there will be more by-products, such as carbon dioxide. When hydrogen is produced from water electricity is used to split the water molecule. If that electricity comes from a renewable energy source such as wind or solar power, then the resulting hydrogen is a renewable, zero emission fuel
The correct answer is dynamo theory. The theory that explains the source of Earth's magnetic field is the dynamo theory. This theory proposes the mechanism of a celestial body such as Earth to generate magnetic field.
The meaningful differences between organisms in a population are genetic. Variations in the genome of members of a population arise through mutation. Occasionally, a mutation occurs in an individual that is beneficial, that helps that organism be better able to survive and repoduce in its current environment.
