Conservation and Dissipation of Energy
This section delves into the law of conservation of energy and explores how energy can be dissipated in various scenarios.
Quote: "Energy can be transferred usefully, stored or dissipated but it cannot be created or destroyed."
This fundamental principle, known as the law of conservation of energy, underpins much of physics and is crucial for GCSE Physics energy revision.
Example: In bungee jumping, energy is dissipated as thermal energy through friction with air particles and the stretching effects of the bungee rope.
The concept of 'work done' is introduced as the transfer of energy from one store to another.
The guide provides practical ways to reduce thermal energy transfer from a house:
- Using insulating materials in walls
- Installing double-glazed windows
- Adding loft insulation
- Constructing buildings with materials of low thermal conductivity
- Building houses with thick walls
Two experiments are described to investigate thermal insulation:
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Effectiveness of different insulating materials:
- Place a small beaker inside a larger one
- Fill the small beaker with hot water
- Use different insulating materials in the larger beaker
- Measure temperature changes over time
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Effect of insulation thickness:
- Wrap a beaker of hot water with varying layers of newspaper
- Measure temperature changes over time for each thickness
Vocabulary: A fluid is defined as a substance in which particles are free to move, encompassing both liquids and gases.
