How do I know what kinematic equations to use when solving a question?

Explanation:

There are 5 kinematic equations, and 5 variables.

Each question will give you 3 variables and ask you to solve for a fourth.

To determine which equation to use, look at which variable is not included in the problem.

For example, if the question does not include time, then you need to use a kinematic equation that does not have t in it.  That would be:

v² = v₀² + 2aΔx

Or, if the question does not include the final velocity, then you need a kinematic equation that does not have v in it.  That would be:

Δx = v₀ t + ½ at²

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