Category: Work, Energy & Power

Introduction Imagine dropping a ball from a height. As it falls, its potential energy decreases while its kinetic energy increases. But the total energy (potential + kinetic) remains constant. This is the essence of the Conservation of Mechanical Energy. Energy is one of the most fundamental concepts in physics. It exists in various forms such…

Introduction When you hold a ball high above the ground, it seems motionless. Yet, if you let go, it immediately begins to fall, gaining speed as it descends. Clearly, the ball at rest in your hand possesses some kind of hidden capacity to do work. That hidden capacity is what physicists call potential energy. Potential…

1. Introduction When you see a speeding car, a flying cricket ball, or a rushing river, one thing is common: motion. And with motion comes energy. The energy possessed by a body due to its motion is called kinetic energy. Kinetic energy (KE) plays a central role in physics because it connects forces, motion, and…

Introduction Whenever you see a car speeding down a highway, a ball rolling on the ground, or a river flowing, one common thing is that they are all in motion. And motion is always associated with energy. The energy possessed by a moving body due to its motion is called Kinetic Energy (KE). It is…

Introduction Physics is filled with elegant principles that connect seemingly different ideas. One of the most beautiful among them is the Work–Energy Theorem, which links the concept of work done by forces to the change in kinetic energy of an object. Think about pushing a heavy box across the floor. You exert a force, the…

1. Introduction In physics, work is one of the most important quantities that connects force with energy. When a constant force acts on an object and displaces it, calculating the work done is simple: W=F⋅d⋅cos⁡θW = F \cdot d \cdot \cos \thetaW=F⋅d⋅cosθ But in real life, forces are rarely constant. Think of: In all these…

Introduction In everyday life, the word “work” often means doing a task: reading a book, cooking, or writing notes. But in physics, the concept of work is much more specific. If you hold a book in your hands for hours, you feel tired, so in everyday sense, you are doing work. But according to physics,…