Energy Stores, Efficiency, and Resources

Flashcards about energy stores, efficiency, power, and energy resources.

Energy Stores

Kinetic, elastic potential, chemical potential, gravitational potential, and thermal.

Energy Transfer Methods

Heating, mechanically, by waves, or by radiation.

System

An object or group of objects.

Change in Thermal Energy Equation

∆E = mc∆θ

Specific Heat Capacity

The amount of energy required to raise the temperature of one kilogram of the substance by one degree Celsius.

Kinetic Energy Equation

Ek = 1/2 mv^2

Elastic Potential Energy Equation

Ee = 1/2 ke^2

Extension of a Spring

The difference between its original length and its new stretched length.

Gravitational Potential Energy Equation

Ep = mgh

Gravitational Field Strength on Earth

10 N/kg

Law of Conservation of Energy

The total energy store of a system remains constant.

Power

The rate at which energy is transferred or the rate at which work is done.

Power Equation

P = E/t or P = W/t

Energy Transfer Rule

Energy can be transferred usefully, stored or dissipated, but cannot be created or destroyed.

Dissipated Energy

It is wasted rather than being stored in useful ways.

Efficiency

A measure of how much useful energy is transferred.

Efficiency Equation

Efficiency = useful energy output /total energy input OR efficiency = useful power output/total power input

Ways to Reduce Unwanted Energy Transfers

By using lubrication or thermal insulation.

Main Energy Resources

Fossil fuels (coal, oil and gas), nuclear fuel, bio-fuel, wind, hydroelectricity, geothermal, the tides, the Sun and water waves.

Uses of Energy Resources

Transport, electricity generation, factories and farms and for homes.

Use of Non-Renewable Resources

It contributes to global warming and other environmental impacts such as acid rain.

Renewable Energy Resource

One that is being (or can be) replenished as it is used.