VIEWS: 186 PAGES: 25 POSTED ON: 5/21/2010 Public Domain
What is a projectile? a. any object that is thrown b. an object that has multiple forces acting upon it c. an object that has only the force of gravity acting upon it d. none of the above An example of projectile motion is (neglecting air resistance)... a. a golf ball being hit b. A water fountain c. A stomp rocket d. All of the above A projectile will follow a parabolic path because... a. The force of gravity acting upon it. b. It loses speed. c. It no longer accelerates. d. All of the above. The definition of range is... a. the horizontal distance traveled of a projectile b. how fast a projectile is moving c. the amount of time a projectile is in air d. None of the above. A water balloon is dropped from the top of the school and is seen to land on the ground 5 seconds after it was released. Approximately how high is the top of the school? a. 19.6 m b. 44.1 m c. 78.4 m d. 122.5 m Stephen shoots a cannonball horizontally off the top of his house. The ball hits the ground 3 seconds later. How tall is his house? a. 19.6 m b. 44.1 m c. 78.4 m d. 122.5 m Imagine yourself throwing a football at various angles; if you wanted to throw the ball as far as you could which angle would you throw it? a. 20 degrees b. 30 degrees c. 45 degrees d. 60 degrees The game is tied, 7-7 and Weak- Arm-Willy is quarterback. What do we, the teammates, advise Willy about making a long pass? a. Wait 3 seconds then throw the ball. b. Throw the ball as hard as you can at an angle of 45 degrees. c. Wait until you get sacked and then sneak me the ball. d. Give the ball to James and let him punt it (soccer does have its advantages) It's the last game of the season…, October 27th , and it's snowing. Actually, it seems more like a blizzard with how hard the wind is blowing. But, we are the dedicated team and are going to get the game in. What do we need to consider when playing the game? a. The team throwing against the wind has the advantage. b. The team throwing with the wind has the advantage. c. The football will act as nothing is different. For projectiles thrown at an angle, and considering air resistance to be negligible, which of the following is true: a. The horizontal component of the velocity is constant b. The acceleration decreases as the projectile moves upward. c. The vertical speed is minimum at the highest point in its trajectory. d. The acceleration is zero at the highest point in its trajectory. a. A and D b. B and C c. C and D d. A and C Emily runs straight off a cliff with a horizontal velocity of 3.35 m/s and falls for 2.12s before landing on the ground. What is the horizontal component of her velocity (in m/s) just before she reaches the ground? a. 11.66 m/s b. 2.35 m/s c. 3.35 m/s d. 4.35 m/s Christina runs straight off a cliff with a horizontal velocity of 2.18 m/s and falls for 1.19s before landing on the ground. What is the vertical component of her velocity (in m/s) just before she hits the ground? a. 11.66 m/s b. 2.35 m/s c. 3.35 m/s d. 4.35 m/s The vertical velocity of a horizontally launched projectile a. increases each second by 10 m/s. b. decreases each second by 10 m/s. c. is constant and remains the same. A rock is thrown horizontally from the top of a cliff with an initial speed of 12 m/s. If the rock hits the ground after 2.0 s what is the height of the cliff? a. 9.8 m b. 19.6 m c. 29.4 m d. 39.2 m Rebecca throws a tennis ball horizontally at an initial velocity of 15 meters/second from a top of a cliff 44 meters high. It will take ___ seconds for the tennis ball to hit the ground. a. 1.5 b. 3 c. 4.5 d. 6 If the initial velocity of a projectile is doubled, it's range will be a. Doubled b. Decreased by a factor of two. c. Quadrupled. d. Decreased by a factor of four. A rude tourist throws a peach pit horizontally with a 7.0 m/s velocity off the balcony of a restaurant. Determine how far the pit will travel horizontally before it strikes the ground 15 m below. a. 105 m b. 2.14 m c. 9.58 m d. 12.24 m The diagram at the right depict the trajectory of a projectile; the position of the projectile after each consecutive second is shown. The arrows depict the horizontal and vertical components of the velocity. Use your understanding of projectiles to find the horizontal velocity at t = 4 s. a. 10 m/s b. 20 m/s c. 30 m/s d. 40 m/s The diagram at the right depict the trajectory of a projectile; the position of the projectile after each consecutive second is shown. The arrows depict the horizontal and vertical components of the velocity. Use your understanding of projectiles to find the vertical velocity at t = 3 s. a. 10 m/s b. 20 m/s c. 30 m/s d. 40 m/s A golfer drives her golf ball from the tee down the fairway in a high arcing shot. When the ball is at the highest point of its flight: a. the velocity and acceleration are both zero b. the x-velocity is zero and the y-velocity is zero c. the x-velocity is constant and the y- velocity is zero d. the velocity is non-zero and the acceleration is zero In the “Bull’s Eye” lab the ball rolled off the table. What was the initial vertical velocity of the ball when it left the table? a. depends on the initial x-velocity b. Depends on the size of the ball c. Unknown; it must be measured d. 0 m/s For a projectile, what is the acceleration in the x-direction? a. depends on initial velocity b. 0 c. Depends on how long it is in the air. d. Depends on the y-acceleration. A bullet is fired horizontally from a gun. At the same time a similar bullet is dropped from the same height. The fired bullet will: a. Hit the ground first b. Hit the ground second c. Hit the ground at the same time as the dropped bullet d. Never hit the ground A mortar shell is fired from the ground at an angle of 60 degrees from the horizontal and with an initial velocity of 200 m/s. What is the vertical velocity of the shell? a. 51.96 m/s b. 173.2 m/s c. 31.96 m/s d. 50 m/s A bullet is fired at an angle of 45 degrees. Neglecting air resistance, what is the direction of acceleration during the flight of the bullet? a. Upward b. Downward c. At an angle of 45 degrees. d. Dependent upon the intitial velocity.