Can these equations be used if acceleration is changing?

No. The standard SUVAT equations are derived assuming constant acceleration. If acceleration is variable, calculus (integration of acceleration functions) must be used instead.

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Core Study Guide

Equations of motion

Solving linear motion variables under constant acceleration.

Kinematics provides the mathematical equations to predict the position, velocity, and time coordinates of objects moving with constant acceleration.

Often referred to as the SUVAT equations, these formulas link displacement (s), initial velocity (u), final velocity (v), acceleration (a), and time (t).

Key Takeaways

•Acceleration is defined as the rate of change of velocity over time.
•The equations of motion only apply when acceleration remains constant.
•Gravity acts as a constant acceleration of 9.8 m/s² downward for free-falling objects.

Core Concepts & Definitions

1Velocity and Acceleration

Velocity is displacement divided by time. Acceleration is the change in velocity divided by time.

•Units of velocity are meters per second (m/s).

•Units of acceleration are meters per second squared (m/s²).

Quick Revision Notes

•In free-fall calculations, acceleration is always downward (take g = -9.8 m/s² if upward displacement is positive).
•At maximum height, the vertical velocity of a projectile is exactly zero.