Understanding the Equations of Motion
Before diving into the equations, let's clarify what each symbol represents. In physics, we use displacement measured in meters, initial velocity and final velocity in meters per second, acceleration in meters per second squared, and time in seconds.
The first equation of motion comes from the basic definition of acceleration. Since acceleration is the rate of change in velocity, we can write it as a = /t. Rearranging this gives us Equation 1: v = u + at. This formula lets you calculate the final velocity when you know the initial velocity, acceleration, and time.
Equation 2 deals with displacement using average velocity. When an object accelerates, its velocity changes constantly. The average velocity is /2, so the displacement formula becomes s = t/2. This equation is particularly useful when you need to find displacement without knowing acceleration.
💡 Think of these equations as your physics toolbox. You don't need to memorize how they're derived - just know when to apply each one. The key is identifying which variables you have and which one you need to find.
Equation 3: s = ut + ½at² comes from combining Equations 1 and 2. You can also visualize this as the area under a velocity-time graph, where displacement equals the sum of a rectangle (ut) and a triangle (½at²).
