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A discussion on how energy can't be created or destroyed in an isolated system, and works an example of how energy is transformed when a ball falls toward the Earth.

An explanation of how LOL diagrams allow us to visually represent what we mean by conservation of energy as well as what we mean by an energy system.

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.

Plotting projectile displacement, acceleration, and velocity as a function of time.

The potential energy between two objects due to long-distance forces can be thought of as being stored in a field. When the objects move due to the field forces, the energy stored in the field decreases

• Determine how each parameter (initial height, initial angle, initial speed, mass, diameter, and altitude) affects the trajectory of an object, with and without air resistance.
• Predict how varying the initial conditions will affect a projectile’s path, and provide an explanation for the prediction.
• Estimate where an object will land, given its initial conditions.
• Determine that the x and y motion of a projectile are independent.
• Investigate the variables that affect the drag force.
• Describe the the effect that the drag force has on the velocity and acceleration.
• Discuss projectile motion using common vocabulary (such as: launch angle, initial speed, initial height, range, time).

Visualising position, velocity and acceleration in two-dimensions for projectile motion.

• Describe a vector in your own words
• Explain a method to add vectors
• Compare and contrast the component styles
• Decompose a vector into components
• Describe what happens to a vector when it is multiplied by a scalar
• Arrange vectors graphically to represent vector addition or subtraction

Energy is a quantitative property of a system that depends on the motion and interactions of matter and radiation within that system. That there is a single quantity called energy is due to the fact that a system’s total energy is conserved, even as, within the system, energy is continually transferred from one object to another and between its various possible forms.

An exploration of how the area under a force vs. position graph equals the work done by the force and solves some sample problems.