Suppose you want to use a single kinematic equation to solve for an unknown kinematic variable (for example, acceleration). How many kinematic variables must you already know the values for?
To use a single kinematic equation to solve for an unknown kinematic variable, you need to know the values of three other kinematic variables. These variables include displacement (Δx or d), initial velocity (v₀), final velocity (v), acceleration (a), and time taken (t).
The five kinematic variables are related to each other through four different kinematic equations:
1. Δx = v₀t + 0.5at²
2. v = v₀ + at
3. Δx = 0.5(v₀ + v)t
4. v² = v₀² + 2aΔx
Each equation allows you to solve for one unknown variable in terms of the others. So to use a single equation, you need to know the values of the other three variables in that equation.
For example, if you want to solve for acceleration (a), you need to know the values of displacement (Δx), initial velocity (v₀), and time taken (t). Plug in the known values into the chosen equation and rearrange it to solve for the unknown variable.
Keep in mind that if you know the values of more than three variables, you can use multiple equations simultaneously to find the desired unknown variable.