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Overview of types of immune responses. Difference between innate and adaptive immunity. Differences between humoral adaptive immunity and cell-mediated adaptive immunity.

Applying Newton's first law to answer some true/false statements about why objects move (or not).

• Identify when forces are balanced vs unbalanced.
• Determine the sum of forces (net force) on an object with more than one force on it.
• Predict the motion of an object with zero net force.
• Predict the direction of motion given a combination of forces.

Figuring out the acceleration of ice down a plane made of ice.

Determining how fast something will be traveling upon impact when it is released from a given height. 

An elaboration on how to use Newton's second law when dealing with multiple forces, forces in two dimensions, and diagonal forces.

An elaboration on some of the common misconceptions in dealing with Newton's Third Law. He also shows how to correctly and reliably identify Third Law force pairs.

In this chapter, we’ll use vectors to expand our understanding of forces and motion into two dimensions. Most real-world physics problems (such as with the game of pool pictured here) are, after all, either two- or three-dimensional problems and physics is most useful when applied to real physical scenarios. We start by learning the practical skills of graphically adding and subtracting vectors (by using drawings) and analytically (with math). Once we’re able to work with two-dimensional vectors, we apply these skills to problems of projectile motion, inclined planes, and harmonic motion.

Basic primer on Newton's First Law of motion.

Newton's Laws of Motion