Skip to content

Salam Academy

Sign in Create account

LearnEdexcel4PH12017 specificationPaper 2P · Paper 2 (all content)Energy resources and energy transfers

Paper 2P · Module

Energy resources and energy transfers

3 subtopics≈ 90 min in total

Start the module: Transfer of thermal energy Open graphing calculator

Transfer of thermal energy
Thermal energy moves from hotter to colder places in three ways. Conduction passes vibrations between particles (and free electrons in metals). Convection carries energy as warm, less dense fluid rises. Radiation is infrared waves, which need no material at all. Dull black surfaces are the best emitters and absorbers; shiny surfaces are the best reflectors.
≈ 30 min
Energy, work and power
Energy is stored in kinetic, gravitational, elastic, chemical, thermal, nuclear and other stores, and transferred by forces, heating, electrical currents and waves. It's never created or destroyed. Work done is energy transferred by a force, $W=Fd$ . Power is the rate of transfer, $P=\dfrac Wt$ . Efficiency is the fraction of input energy that ends up useful.
≈ 35 min
Energy resources
Most of our energy comes, directly or indirectly, from the Sun: fossil fuels, biofuels, wind, waves, hydroelectric and solar. Tides, geothermal and nuclear fuel are the exceptions. Renewable resources won't run out; non-renewable ones will. Every resource is a trade-off between cost, reliability, scale and pollution.
≈ 25 min