# DDP Chapter 2

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# Links for the Second Chapter

This video discusses the definition of acceleration.

This video shows you what you can learn from a velocity versus time graph.

This video shows you how to calculate acceleration from a velocity versus time graph.

This video shows you how mass affects acceleration according to Newton’s Second Law.

This video shows you that Newton’s Second Law applies even when it is only the DIRECTION that is changing.

This video shows that in free fall, everything falls with the same acceleration.

This video gives you the solution to three free-fall problems. In his equations, he uses “g” instead of “a” (because the acceleration is due to gravity), “vi” instead of “v0”, and delta_y instead of delta_x (since the problems involve rising and falling).

This video discusses the difference between mass and weight using the equation given in the book.

This video discusses the difference between mass and weight using the difference between lifting and pushing a car.

Extra Practice Problems
Here are the extra practice problems for Chapter 2. The solutions are here.