Energy transfers: แบบฝึกหัด

• a.Wind
• b.Nuclear fuel
• c.Bio-fuel
• d.Geothermal

• a.\(2160\text{ J}\)
• b.\(192\text{ J}\)
• c.\(168\text{ J}\)
• d.\(15\text{ J}\)

• a.Higher potential difference allows the electricity to travel at a higher frequency to reach consumers faster.
• b.Higher potential difference results in a lower current, which reduces the energy lost as heat in the cables.
• c.Higher potential difference increases the resistance of the cables, slowing down the charge flow.
• d.Higher potential difference ensures that the power stations can produce more energy from the same amount of fuel.

• a.

  All energy is eventually destroyed through friction.

• b.

  The total energy increases if work is done by the system.

• c.

  There is no net change to the total energy of the system.

• d.

  The total energy decreases as energy is dissipated into the surroundings.

• a.\(400\text{ W}\)
• b.\(800\text{ W}\)
• c.\(200\text{ W}\)
• d.\(1600\text{ W}\)

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