Projectile Motion

• Projectile- only force on object is gravity• Trajectory- projectile’s path

• Independence of Motion– Velocity and acceleration are vectors– Combination of x and y motion

Solving Projectile Motion Problems

• Break problem into 2 problems. X and Y.• Vertical motion has acceleration of gravity ALWAYS.

(Acceleration = -9.8 m/s²)• Air drag is neglected, so X has no acceleration. This

means that velocity in X direction DOES NOT change.

• Vertical and horizontal motion is connected through time. The time is the SAME in both X and Y.

Equations

• vavg =d/t• Vf 2 = Vi 2 + 2ad • a= (Vf-Vi) / t• d = ½ at² + Vit

• A baseball is dropped from the upper deck, which is 50 m up. How long does it take to hit the ground? How far from the upper deck will it land?

• A baseball is thrown horizontally at 15 m/s from the upper deck, which is 50 m up. How long does it take to hit the ground? How far from the upper deck will it land?

• A car drives off a cliff that is 3,550 ft high. The car lands 20 seconds later, 0.5 miles from the cliff. How fast was the car going in mph?