Work, Energy, and Power – Meaning, Formulas, and Examples

1️⃣ Work

What is Work in Physics?
Work is done when a force is applied on an object and the object moves in the direction of the force .

Formula:

Where:

• W = Work done
• F = Force applied
• d = Displacement of the object
• θ = Angle between force and displacement

Example:

• Pushing a trolley forward.
• Lifting a bucket from the ground.

Note: If there is no displacement, no work is done (even if you apply force).

2️⃣ Energy

Meaning:
Energy is the capacity to do work .

Types of Mechanical Energy:

1. Kinetic Energy (KE) – Energy due to motion
   Formula:

   
2. Example: Moving car, running athlete.

3. Potential Energy (PE) – Energy due to position or height
   Formula:

   
4. Example: Water stored in a dam, stretched bow.

3️⃣ Power

Meaning:
Power is the rate at which work is done .

Formula:

Where:

• P = Power
• W = Work done
• t = Time taken

Example:
Two people lift the same weight, but one does it faster – that person has more power.

Summary Table:

Concept	Meaning	Formula	Unit	Example
Work	Force × displacement		Joule (J)	Lifting a bag
Kinetic Energy	Energy of motion		Joule (J)	Moving car
Potential Energy	Energy of position		Joule (J)	Water in dam
Power	Rate of work		Watt (W)	Fast lifting