Compound motion Three types of motion: Vertical motion Horizontal motion Combination of 1. and 2. Projectile motion An object thrown into the air Basic observations: Gravity acts at all times Acceleration (g) is independent of the object’s motion

Projectile motion Vertical projectile Slows going up Stops at top Accelerates downward Force of gravity acts downward throughout Horizontal projectiles Horizontal velocity remains the same (neglecting air resistance) Taken with vertical motion = curved path http://www.physicsclassroom.com/Class/vectors/u3l2a.html

2.5 Compound Motion Horizontal Projectiles: Gravity is constantly working on a horizontal projectile- increasing its downward velocity If we ignore air resistance, horizontal velocity remains CONSTANT The combination of these two paths results in a curved trajectory

2.5 Compound Motion Since horizontal motion is independent of gravity, a horizontal projectile will hit the ground at the same time as an item dropped from the same height

2.5 Compound Motion Horizontal Projectiles: When an object is launched at an angle: gravity is always pulling downward first half of path is identical to second half of path Combination of these 2 forces results in a trajectory in the shape of a parabola

2.5 Compound Motion Horizontal Projectiles: The second half of a parabola is identical to the first half ignoring air resistance

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