Mechanics → Kinematics of Particles → Derivation of Equations of Motion
Derivation of Equations of Motion
First Equation
Starting from:
$$ a = \frac{dv}{dt} $$
Assuming constant acceleration:
$$ dv = a \, dt $$
Integrating:
$$ \int dv = \int a \, dt $$
$$ v = u + at $$
Second Equation
We know:
$$ v = \frac{dx}{dt} $$
Substitute $v = u + at$:
$$ \frac{dx}{dt} = u + at $$
Integrating:
$$ x = ut + \frac{1}{2}at^2 $$
Third Equation
From:
$$ v = u + at $$
Eliminate $t$:
$$ t = \frac{v - u}{a} $$
Substitute into second equation:
$$ x = ut + \frac{1}{2}at^2 $$
After simplification:
$$ v^2 = u^2 + 2ax $$