So at this point, we've learned a bit about some important vocabulary we can use to speak more specifically about the motion of objects: distance and displacement, speed and velocity, acceleration, and forces. We've seen how Newton's first law (

an object at rest will stay at rest and an object in motion will stay in motion unless acted on by an unbalanced force

) applies to situations like standing on a stopping bus, letting go of a moving skateboard, and getting tackled without good protective gear.

We've also seen how the second law of motion applies. The force that we apply on an object is directly proportional to how quickly it accelerates 

(also items with very little mass accelerate more given the same force than items with lots of mass). 

We've covered a lot already but there's probably a lot of things that don't make perfect sense yet — questions still unanswered.

Based on what you know already, do your best to answer this question with a detailed explanation that really gets into the physics based on the video. 

Learn how free body diagrams can be used to model unbalanced forces on an object.

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