Honors Physics Acceleration and Projectile Review Guide Major Concepts 1 D Motion on the horizontal 1 D motion on the vertical Relationship between velocity and acceleration Difference between constant velocity and constant acceleration Characteristics of a projectile Horizontal motion of an horizontally launched projectile Vertical motion of an horizontally launched projectile Projectiles that are launched at an angle Acceleration of a projectile on the horizontal Acceleration of a projectile on the vertical Relationship between launch angle, height, range and time Labeled diagram of the trajectory of launched horizontally projectile Effect of gravity and air resistance on a projectile True or False Correct any false statement 1. Any object has the potential to be a projectile. 2. On lift off, a rocket is a projectile. 3. The acceleration due to gravity influences both the horizontal and vertical component. 4. The horizontal and vertical components are independent of each other. 5. The greatest range will occur when the launch angle is 45 6. If the horizontal velocity doubles, the time doubles. 7. Hang time is twice the time it takes to reach maximum height. 8. Projectiles launched at complementary angles will have the same range. 9. For an upwardly throw object, the greatest velocity is at the top of the trajectory. 10. For an object launched horizontally, the initial velocity on the y is 0 m/s. 11. An upwardly thrown object may have an initial velocity of 0 m/s. 12. If the velocity vector and the acceleration vector are occurring in the same direction then the object is slowing down. 13. An object in free fall is affected by gravity. 14. The horizontal and vertical components of a projectile are independent of each other. 15. A dropped object and an object launched from the same height will hit the ground at the same time. Practice Multiple Choice 1. A bullet is fired at an angle of 45. Neglecting air resistance, what is the direction of acceleration during the flight of the bullet? a. Upward b. downward c. dependent on initial velocity 2. For a projectile, what is its acceleration in the horizontal direction? a. Depends on initial velocity b. Depends on time in the air c. Depends on the velocity on the y axis d. 0m/s 2
3. A 10 kg object and a 100 kg object of the same size are dropped from the roof of a building. Which will hit the ground first? (Neglect air resistance) a. they will hit at the same time b. the 10 kg object c. the 100 kg object d. cannot be determined from given information 4. Which of the following is an example of projectile motion? a. a bullet being fired from a gun b. a jet lifting off a runway c. a space shuttle orbiting Earth d. dropping an aluminum can into the recycling bin 5. A ball is rolled off the edge of a horizontal table. The ball has an initial speed v o and lands on the floor some distance from the base of the table. Which of the following statements concerning the fall of the ball is false? a. the time of the flight depends upon the height of the table b. one of the components of the final velocity will be v o c. the ball will accelerate d. the ball will have a longer flight time if v o is increased e. the ball falls due to the force of gravity 6. If air resistance can be neglected, what happens to the horizontal velocity of a basketball as it is thrown to the basket from the free throw line? a. It increases b. It decreases c. Increases while the ball is going up and decreases as the ball is coming down d. Decreases while the ball is going up and increases as the ball is coming down e. Stays constant 7. Which trajectory has the greatest horizontal velocity? a. V1 b. V2 c. V3 d. they are all equal 8. Which trajectory has the greatest vertical velocity? a. V1 b. V2 c. V3 d. they are all equal 9. An airplane pilot is moving with a velocity v and drops a package. In the absence of air resistance where is the package relative to the airplane at the moment it hits the ground? A Behind the airplane B In front of the airplane
C Directly below the airplane D Cannot be determined without knowing how high the plane is E Cannot be determined without knowing the distance traveled by the airplane 10. Which of the following projectiles made the graph below a. a marble the rolls off of a table b. a football kick at the beginning of the ball game c. a cannon ball launched from a cannon at an angle of 30 to the horizontal d. both b and c 11. A ball is launched horizontally from the top of a cliff with an initial velocity of 20 m/s. The trajectory of the ball is shown below. Express your understanding by filling in the blanks. Problems 1. A movie stunt driver on a motorcycle speeds horizontally off a 50.0 m high cliff. How fast (in km/h) must the motorcycle leave the cliff top if it s to land on the level ground below at a distance of 90.0 m from the base of the cliff? 2. A ball rolls off a desk at a speed of 3.0 m/s and lands 0.40 seconds later. a) How far from the base of the desk does the ball land? b) How high is the desk? c) What is the speed and angle of impact? 3. A rescue pilot drops a survival kit while her plane is flying at an altitude of 2000.0 m with a forward velocity of
100.0 m/s. If air friction is disregarded, how far in advance of the starving explorer s drop zone should she release the package? Minion Motion 1. A Minion is thrown straight up and reaches his apex 2.4 seconds later. a. Describe the Minion s motion in terms of velocity and acceleration. b. Why is the Minion s initial velocity a non zero value? c. Calculate the initial velocity of the Minion. d. How high did the Minion go? 2. Next, the Minion fell horizontally out of a 20.3m high window with an initial velocity of 13.5 m/s. a. Describe the Minion s motion in terms of velocity and acceleration. b. How long did it take the Minion to hit the ground? c. How far from the window did the Minion land? d. Sketch a vector diagram of the Minion as he fell out of the window.
3. Explain why the Minion above is not a projectile.