2 The Quiz 8 questions Some multiple choice Most short answer Some questions have multiple partsMUST show all workYou can earn partial credit
3 Summary of PHET Simulation Results http://phet. colorado If air resistance is ignored, changing the object being thrown does NOT affect the motion.The velocity (speed and angle or direction) does affect the motion (range, highest height).Projectiles launched at complimentary angles (angles that add up to 90 degrees) will travel over the same horizontal distance. This is only true when the projectile lands at the same height it was launched from.
4 Thinking about projectiles… What is a projectile?What is the shape of a projectile’s trajectory? (you should be able to sketch the trajectory or path of a projectile for any problem)How do we think of projectile motion so that it is easier to analyze?
5 2 motions in one (ignore air resistance) Horizontal motionNo accelerationVelocity is always constantVertical motionAlways has acceleration (a = g = -9.8 m/(s^2))The vertical motion is exactly like the motion of an object in free fallHorizontal and vertical motion are connected by the time
6 Question 1:A baseball is thrown with an initial horizontal velocity of 15 m/s and an initial vertical velocity of 10 m/s.What angle was the ball thrown at?What is the total initial velocity (v)?What is the highest height that the ball will reach?How far will the ball travel horizontally?What is the ball’s hangtime?What is the final velocity of the ball when it hits the ground?Sketch v, vx, and vy at the starting point, highest point, and ending point.
7 Draw a diagram showing the trajectory of the marble. Question 2: A marble rolls horizontally off the edge of a flat table with a speed of 0.8 m/s. If the table is 1.2 m tall how long was it in the air?Draw a diagram showing the trajectory of the marble.
8 Question 3: Rafid accidentally drops his Nintendo DS while riding in a small airplane. If the plane was at a height of 150 meters and the DS travels 1300 meters before hitting the ground, how fast was the plane moving?