There are several formulas used to determine the acceleration of an object moving in a straight line, depending on the specific motion. Here are two common formulas:

1. Average Acceleration:

If you know the initial velocity (u), final velocity (v), and the time interval (t) during which the velocity changes, you can calculate the average acceleration (a) using the formula:

a = (v - u) / t

2. Instantaneous Acceleration:

Instantaneous acceleration refers to the acceleration of an object at a specific instant in time. It is the limit of the average acceleration as the time interval approaches zero. If you have a function that describes the velocity of an object (v(t)), you can find the instantaneous acceleration by taking the derivative of the velocity function with respect to time:

a = dv/dt

Remember to use consistent units for velocity (e.g., m/s) and time (e.g., seconds) to obtain acceleration in appropriate units (e.g., m/s²).