Work and Energy in Science

Work is done when a force applied on an object makes it move in the direction of the force. If an object does not move, then no work is said to be done. The formula for work is Work = Force × Displacement and the unit of work is joule (J).

Energy is the ability to do work. Anything that can do work has energy. One type of energy is kinetic energy, which an object has because it is moving. Its formula is Kinetic Energy = 1/2 × m × v², where m is mass and v is velocity. Another type is potential energy, which is the stored energy of an object due to its height or position. Its formula is Potential Energy = m × g × h, where m is mass, g is gravity (9.8 m/s²), and h is height.

The work-energy theorem says that when work is done on an object, its energy increases or decreases. For example, when work is done to make an object move faster, its kinetic energy increases. The law of conservation of energy says that energy cannot be created or destroyed; it only changes from one form to another, but the total energy remains constant.

Power tells how fast work is done. The formula for power is Power = Work / Time and its unit is watt (W).