Energy Transfers and Conservation Principles

These flashcards cover key concepts in energy transfers, conservation of energy, and efficiency in various systems.

What energy transfer happens when a moving car brakes to a stop?

Kinetic energy to Thermal energy (due to friction in brakes).

Identify the energy stores and transfers when stretching and releasing a rubber band.

Elastic potential energy to Kinetic energy to Thermal energy.

State the principle of conservation of energy.

Energy cannot be created or destroyed, only transferred or stored differently.

A machine uses 500 J of energy and 300 J becomes useful. What is its efficiency?

60%.

Describe the energy transfers in a kettle.

Electrical energy to Thermal energy (heats water) plus some sound energy.

Why is metal a good conductor of heat?

Metal particles vibrate and transfer heat energy efficiently through conduction.

Why do black surfaces absorb and emit radiation better than white or shiny surfaces?

Black surfaces are better absorbers and emitters of thermal radiation.

What is the formula linking work done, force, and distance moved?

W = F × d

What is the formula for gravitational potential energy (GPE)?

GPE = m × g × h

What energy transfers happen in a coal-fired power station?

Chemical energy to Thermal energy to Kinetic energy to Electrical energy.