Energy Lecture Notes

Flashcards based on lecture notes about energy, its forms, transfer, and resources.

What is kinetic energy?

Energy of a moving object.

What is gravitational potential energy?

Energy an object has when raised above the ground.

What is elastic potential energy?

Energy in elastic objects when stretched or compressed.

What is internal (thermal) energy?

Total kinetic and potential energy of all the particles.

What is chemical energy?

Energy in chemical bonds.

What is nuclear energy?

Energy in the nucleus of an atom.

What is magnetic energy?

Energy a magnetic object has when near a magnetic field.

What is electrostatic energy?

Energy a charged object has when near another charged object.

What is a closed system?

Total energy remains constant, but energy can be transferred between its stores. Energy can't escape or enter.

What are the ways energy can be transferred between stores?

Heating, radiation, electrical work, and mechanical work.

What are thermal conductors?

Allow thermal energy to move through them easily (e.g., metals).

What are thermal insulators?

Do not allow thermal energy to move through them (e.g., wood, fibreglass).

What does the rate of thermal energy transfer depend on?

Temperature difference, thickness of material, and thermal conductivity.

How do hydroelectric dams work?

Water is collected in a reservoir at the top of a hill and flows downhill, turning turbines connected to generators.

How do tidal barrages work?

Water is trapped in a barrage during high tide and released through turbines.

What is biofuel?

Any fuel obtained from living organisms, considered renewable and carbon neutral.

How do solar panels work?

Use energy from the sun to create electrical currents directly.

How do wind turbines work?

Wind turns a turbine which turns a generator, converting kinetic energy into electrical energy.

What is the law of conservation of energy?

Energy cannot be created or destroyed, only transformed.

How is efficiency calculated?

Useful energy out divided by total energy in.

What is wasted energy?

Energy not usefully transferred.

What are the advantages of renewable energy resources?

Can be made as quickly as it's used, doesn't release CO2, and is non-polluting.

What are characteristics of Finite energy resources?

Can't be made at the same rate it's used, readily available/cheap, but short-term setup, and heavily polluting.

What are physics prefixes?

Tera (T) = x10^12, Giga (G) = x10^9, Mega (M) = x10^6, Kilo (K) = x10^3, Centi (c) = x10^-2, Milli (m) = x10^-3, Micro (μ) = x10^-6, Nano (n) = x10^-9