Term 1 Class 6
The City School
Worksheet Number: Science 1.11.2
Topic: Sound and Energy
Name: ___________________ Class: ___________
No system is perfect. Whenever there is a change in a system, energy is transferred and some of that energy
is dissipated.
Dissipation is a term that is often used to describe ways in which energy is wasted. Any energy that is not
transferred to useful energy stores is said to be wasted because it is lost to the surroundings. Electrical
cables warming up are a good example of this. It is not useful to have hot wires behind a television as energy
is dissipated to the surrounding air.
In a mechanical system, energy is dissipated when two surfaces rub together. Work is done against friction
which causes heating of the two surfaces - so the internal (thermal) energy of the surfaces increases. Adding
lubricant between the surfaces reduces this friction and so less heat is wasted, like on a conveyor belt for
example.
In an electrical context, new types of components can be more energy-efficient. For example, using LED light
bulbs as opposed to filament lamps causes less energy to be wasted.
Q1. How does friction contribute to energy dissipation in mechanical systems?
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Q2. Provide examples of everyday mechanical systems where energy dissipation is significant.
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Q3.
Term 1 Class 6
The first one has been done for you.
Q4. Fill in the blanks with the most suitable word.
A. Energy dissipation refers to the gradual _______________ of energy from one form to another, often
resulting in the release of heat.
B. In mechanical systems, friction plays a significant role in causing _______________ energy dissipation
as objects rub against each other.
C. The process of _______________ involves the transfer of heat energy through direct contact between
particles in a substance.
D. Electrical circuits with high resistance tend to experience more _______________ energy dissipation
in the form of heat.
E. In fluid dynamics, the viscosity of a fluid causes internal _______________ and subsequent energy
dissipation as the fluid flows.
F. Energy dissipation can lead to inefficiencies in renewable energy systems, such as _______________
panels, reducing their overall output.
G. Minimizing energy dissipation is crucial for improving the overall _______________ of systems and
increasing their efficiency.
