Here's a simple video of a straw (a light weight object) falling.
Note the way the timing (how fast) and number of frames (how many images) suggest the weight visually. (A heavy object will use different timing and patterns).
Your final version should look something like this - the X-sheet mapping the frames, your pictures/drawings, and the rate/timing (how long they are on screen).
Feel free to change the timing to see how different timing changes the "weight" and properties of your object.