Learners explore projectile motion as they use a catapult to protect a castle from attack.
After completing this tutorial, you will be able to complete the following:
The concept of projectile motion is generally studied as a part of physics. Projectile motion integrates the knowledge of force, motion, energy, and Newton's laws. Projectiles are examples of two-dimensional motion, with a horizontal component and a vertical component. Studying projectiles requires an investigation of the relationship between gravitational acceleration and the projectile's initial velocity.
An object that is launched into the air at some angle is a projectile. Examples of projectiles include a golf tee shot, a thrown or hit baseball, or a bullet shot from a pistol. Gravity and air resistance affect the flight paths of these projectiles. A projectile launched at an angle would continue in a straight line at a constant velocity if gravity were not present. However, gravity makes the projectile accelerate to Earth. This shows us why a projectile launched at an angle follows a parabolic trajectory. This parabolic shape is the result of two types of independent motion, horizontal and vertical.
In the example of a catapult, initial velocity is determined by how much the catapult is stretched. The catapult's potential energy in the stretched rope is then converted to kinetic energy of the projectile. The angle at which the object is launched determines how its velocity is divided between its horizontal and vertical components. The variables to be considered during projectile motion experiments include: range, time, initial velocity, and angle. The range is the horizontal distance the projectile moved. Time is the amount of time that the object is in the air. Angle refers to the angle of launch of the projectile. As the angle of launch is manipulated, it will be discovered that at 45?, the horizontal and vertical components are equal to each other maximizing the range of the projectile. By increasing the launch angle, the vertical component of velocity will go up while the horizontal component decreases. This means that the projectile will stay in the air longer and climb to a greater height.
|Approximate Time||20 Minutes|
|Pre-requisite Concepts||angle, gravity, velocity|
|Type of Tutorial||Concept Development|
|Key Vocabulary||acceleration, air resistance, angle|