YOU ARE LEARNING:
Energy Waste
Energy Waste
When we transfer energy, we must accept that some energy is wasted as heat.
The conservation of energy principle states that energy cannot be created nor destroyed. Now, can energy be "wasted"?
Imagine a pan of boiling water on an electric hob. The electrical energy is transferred to heat energy to boil the water. Some of this energy is wasted. What happens to most of that wasted energy?
Energy is wasted when heat is lost to the surroundings. What do you think we might call that process?
Do you think the energy transfer chemical(10000J)→kinetic(10000J) is possible in a real-life situation?
In all systems, some energy is dissipated and stored in less useful ways. What useless type of energy do you think is dissipated in a washing machine?
Can you work out how much energy is wasted in a washing machine with the following energy transfer electrical(7000J)→kinetic(4000J)+heat(2500J)+sound ?
Many devices work, using mechanical energy, which depends on movement and position of an object. Can you guess what types of energy contribute to the mechanical energy of an object? Pick all the options you think are correct.
You can select multiple answers
Mechanical processes dissipate energy in the form of heat. Which one of these options do you think is the reason for that?
When the astronauts returned from the Apollo 11 mission from the Moon, one of the concerns was that the capsule would burn up in the atmosphere. Imagine the capsule falling down to Earth on return. The gravitational potential energy is transferred as kinetic, and heat energy which is wasted. What causes heat dissipation?
A) Air Resistance B) Gravity C) Acceleration
What might cause an electrical cable to heat up and dissipate heat energy?