During energy transfers in everyday devices, some of the input energy is always dissipated. What does it mean when we say energy is "dissipated"?
It is completely destroyed and no longer exists.
It is converted entirely back into the original useful form of energy.
It spreads out into the surroundings and becomes less useful.
It increases the total amount of energy in the system.
533 exam-style questions on CIE IGCSE Physics 1.7 Energy, work and power, covering 1.7.1a Energy stores and energy transfers, 1.7.1b Conservation of energy, 1.7.1c Kinetic and gravitational potential energy, 1.7.2 Work done, 1.7.3 Energy resources, 1.7.3a Energy resources and electricity generation, 1.7.3b Nuclear fusion as an energy source, 1.7.3c Efficiency of energy transfer, and 1.7.4 Power. Each one has a worked solution and a mark scheme showing where the marks go.