Why are energy-efficient devices useful?
Answer and explanation
Correct answer: They use less electricity for the same task
An energy-efficient device provides the required service while consuming less electricity than a comparable less-efficient device. Lower consumption helps conserve energy and can reduce operating costs, although actual savings depend on usage, tariffs, and the appliance. The other options contradict efficiency because greater consumption, increased wastage, or always higher bills do not define an energy-efficient device.
Frequently asked questions
What is the correct answer to this question?
They use less electricity for the same task
Why is this the correct answer?
An energy-efficient device provides the required service while consuming less electricity than a comparable less-efficient device. Lower consumption helps conserve energy and can reduce operating costs, although actual savings depend on usage, tariffs, and the appliance. The other options contradict efficiency because greater consumption, increased wastage, or always higher bills do not define an energy-efficient device.
Which subject and chapter does this question cover?
This is a Class 9 Science question. Chapter: Earth as a System: Energy, Matter, and Life. Topic: Energy flow in Earth systems.
