Energy forms and changes – heat flow and energy chains
Integrated ScienceEnergyAges 11–12
Loading…
Sign in to playOn the Intro screen, drag an iron block, a brick, a beaker of water and a beaker of cooking oil onto two burners that heat or cool, stack blocks or drop them into a beaker, and measure temperatures with thermometers: heat flows from hotter to colder objects and into the air, objects with a smaller heat capacity warm up faster, and water at 100 °C turns into steam. On the Systems screen, build a chain from a source (faucet, sun with clouds, kettle on a stove, cyclist) through a converter (generator, solar panel) to an energy user (incandescent bulb, fluorescent bulb, electric kettle, fan) and watch energy chunks change form at each stage, with the wasted part released as heat. Adapted from the "Energy Forms and Changes" simulation by PhET Interactive Simulations, University of Colorado Boulder (CC BY 4.0); rewritten.
Lesson: Energy transfers and wasted energy
What it shows
The "Energy forms and changes" simulation supports the topic of energy, in the lesson on energy transfers and wasted energy. Students carry out heat transfer experiments and build energy transfer chains themselves, seeing clearly that energy only changes form and is never simply lost.
How to use
On the Intro screen, students drag the iron block, brick, beaker of water and beaker of cooking oil onto two burners, slide a knob up to heat or down to cool, stack blocks or drop a block into a beaker, then place thermometers to read the temperature of each object. On the same burner setting the iron block warms up much faster than the water because its heat capacity is smaller; once the water reaches 100 °C its temperature stays constant and the water turns into steam. Switching on the energy chunks shows thermal energy flowing from the burner into the objects, from hotter to colder objects and out into the air. On the Systems screen, students choose a source (a faucet, the sun with clouds, a kettle heated on a stove, or a cyclist who needs feeding), a converter (generator or solar panel) and an energy user (incandescent bulb, fluorescent bulb, electric kettle or fan). The energy chunks change color with the form of energy: mechanical, electrical, light, chemical and thermal; every stage wastes some energy as heat, and the data panel shows that the total energy in always equals useful plus wasted energy.
Parameters you can change
- Screen Intro (burners, objects, thermometers), Systems (energy chain)
- Show energy chunks
- Energy source (Systems screen) Faucet, Sun, Kettle heated on a stove, Cyclist
- Converter (Systems screen) Generator, Solar panel
- Energy user (Systems screen) Incandescent bulb, Fluorescent bulb, Electric kettle, Electric fan
Questions to explore
- When the cyclist lights up the bulb, which forms does the energy pass through?
- If you put the iron block and the beaker of water on two burners at the same setting, which warms up faster, and why?
- Why does an incandescent bulb waste more energy than a fluorescent bulb, and where does the wasted energy go?
