An inline skater traveling in a straight line goes from 3 m/s to 9 m/s in 3 seconds. What is the acceleration?

In physics terms, acceleration, a, is the amount by which your velocity changes in a given amount of time.

Given the initial and final velocities, v_i and v_f, and the initial and final times over which your speed changes, t_i and t_f, you can write the equation like this:

In terms of units, the equation looks like this:

a = (distance/time) / time = distance/time²

Plugging in the numbers, you get the following:

a = (9 m/s -3 m/s) / 3s

a = (6 m/s) /3s

a = 2m/s²

The acceleration is 2 meters per second².

Tip: Here's How to Calculate Time and Distance from Acceleration and Velocity from Dummies.com.