NCERT Work and Energy – Class 9 Science
The chapter “Work and Energy” in NCERT Class 9 Science introduces the concepts of work, energy, and power, which are fundamental in Physics. Work is done when a force is applied on an object and it moves in the direction of the force. Students learn the conditions for work, the formula for calculating work, and the difference between positive, negative, and zero work.
The chapter also explains energy, the capacity to do work, including its forms such as kinetic energy (energy of motion) and potential energy (stored energy). The work-energy theorem is discussed to show how work done on an object changes its energy.
Additionally, the chapter covers power, the rate at which work is done, and introduces mechanical efficiency. Real-life examples, such as lifting objects or moving vehicles, help students understand these concepts clearly. This chapter is essential for building a strong foundation in mechanics.
