You might be surprised to know that, with these three units, we can derive the majority of the other units that we need. As you have probably guessed by now, we can just derive the units of a new quantity by looking at the formula or how it is defined. Let us do that for several of the things that we have already talked about. Namely, let us do this for speed, acceleration, and force. Derived Units Speed Recall the definition of average speed.
Average speed is defined as distance over time.
Remember, we are now using S.I. units. Both are distance over time. To answer this question, think of the difference between speed and velocity. They differ only in that we need to specify a direction when we are talking about velocity. Acceleration Recall the definition of acceleration.