Projectile Motion
Guiding Question
How can we depict the motion of a projectile?
How can we determin the optimum angle for launching a projectile the farthest distance?
What is the difference between acuracy and precision?
Overarching Lab: Engineering a Catapult
Engineers must master the science and math concepts behind a given technology before they can successfully design and build products that meet the design criteria of their client. The ultimate demonstration of understanding is the ability to apply the knowledge successfuly. Throughout this unit you will be working on a single overarching lab where through engineering a functional catapult you will learn the concepts of projectile motion.
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Objectives/Parameters:
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designing and building a catapult that can launch a tenis ball a minimum of 5 meters
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base should be 36x15
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LEARNING TARGETS
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Engineers must master the science and math concepts behind a given technology before they can successfully design and build products
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Describe how force affects the motion of a projectile.
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Explain and compare the meanings of accuracy and precision.
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Explain the optimum angle for launching a projectile the farthest distance
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apply understanding of projectile motion
Vector and Scalar Quantities
Vector Quantity
must have both magnatude and direction​
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Example: velocity is a vector quantity because it has a magnitude (m/s) and a direction
Scalar Quantity
can be described completly with only magnitude​
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Example: speed is a scalar quantity because it can be described completly by it's magnitude alone (m/s)
Velocity Vectors
Question: If an airplane is traveling at 100 km/hr relative to the surrounding air how will a 20 km/hr wind impact its velocity relative to the ground?
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Answer: Remember all motion is relative. Just because the plane is traveling at 100 km/hr relative to the surrounding air does not mean it is traveling at 100 km/hr relative to the ground. If the plain is traveling in a 20 km/hr headwind then the plane will be traveling 80 km/hr relative to the ground.
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If the plane is traveling in a 20 km/hr tailwind then the plane will be traveling 120 km/hr relative to the ground
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20 km/hr tailwind
100 km/hr relative to the surrounding air
Resultant
120 km/hr relative to the ground
If the plane is traveling in a 20 km/hr crosswind we now have two vectors acting perpendicular to each other. This will result in a diagonal vector called the Resultant (go figure) then the plane will be traveling 120 km/hr relative to the ground
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20 km/hr headwind
100 km/hr relative to the surrounding air
Resultant
80 km/hr relative to the ground