<aside> ⚡ Kinetic energy: $E_k$ is the energy an object has due to its motion. An object's kinetic energy is directly related to its mass and the square of its speed, according to the following relationship: $E_k=\frac{1}{2}mv^2$
where $m$ is the mass, and $v$ is the speed
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Total work done on an object by an external force = change its kinetic energy
$W=\frac{1}{2}mv^2_f - \frac{1}{2}mv^2_i$ $W = E_{kf} - E_{ki}$ $W = \triangle E_k$