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Introduction to bacteria

The amount of effort saved when using machines is called mechanical advantage (MA). Simple machines use mechanical advantage as a key property to their functionality, helping humans perform tasks that would require more force than a person could produce. We will use the lever as an example of a simple machine to illustrate the concept of mechanical advantage.

• 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.

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

In this unit we will learn how these factors can affect the output of a simple machine. We will also learn about the difference between ideal mechanical advantage (IMA) and actual mechanical advantage (AMA), and how to apply your knowledge to calculate the efficiency of various simple machines.

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.

• 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.

In this lesson you will learn about:

• Simple machines
• Be able to identify different kinds of machines
• Identify classes of levers and pulleys
• Determine mechanical advantage of a lever and pulleys
• Understand and determine the advantage of an inclined plane
• Describe and determine the advantage of a screw jack
• Describe and determine the advantage of a wheel and axel
• Describe and determine the advantage of a hydraulic press