Unformatted text preview: MasteringPhysics: Assignment Print View 3/2/08 4:53 PM [ Print View ] PHYS 2211 ABCDE Spring 08
MP20: Projectile Motion
Due at 11:59pm on Tuesday, February 12, 2008
View Grading Details Projectile Motion Tutorial
Learning Goal: Understand how to apply the equations for 1-dimensional motion to the y and x directions separately in order to derive standard formulae for the range and height of a projectile. A projectile is fired from ground level at time with respect to the horizontal. It has an initial speed problem we are assuming that the ground is level. , at an angle . In this Part A Find the time Hint A.1 it takes the projectile to reach its maximum height. A basic property of projectile motion It is important to understand that the motion in the y direction is independent of the motion in the x direction because these directions are orthogonal (at right angles) to each other. Part A.2 What condition applies at the top? Part not displayed Part A.3 Vertical velocity as a function of time . Find an expression for the projectile's vertical velocity as a function of time, Part A.3.a Initial velocity in y direction Part not displayed Express your answer in terms of , ANSWER: , , and , the acceleration due to gravity. = Answer not displayed Hint A.4 Putting it all together Hint not displayed Part A.5 A list of possible answers Part not displayed Express ANSWER: in terms of = , , and (the magnitude of the acceleration due to gravity). Part B Find , the time at which the projectile hits the ground. Two possible approaches Part not displayed Part B.2 Some needed kinematics Part not displayed Hint B.3 Solving for Part B.1 http://session.masteringphysics.com/myct/assignmentPrint?assignmentID=1114140 Page 1 of 3 MasteringPhysics: Assignment Print View 3/2/08 4:53 PM Hint not displayed Express the time in terms of ANSWER: = , , and . Part C Find , the maximum height attained by the projectile. Equation of motion Hint not displayed Part C.2 When is the projectile at the top of its trajectory? Part not displayed Hint C.3 Finding Hint not displayed Express the maximum height in terms of ANSWER: = , , and . Hint C.1 Part D Find the total distance Hint D.1 (often called the range) traveled in the x direction; in other words, find where the projectile lands. When does the projectile hit the ground? Hint not displayed Part D.2 Where is the projectile as a function of time? Part not displayed Hint D.3 Finding the range Hint not displayed Part D.4 A list of possible answers Part not displayed Express the range in terms of ANSWER: = , , and . The actual formula for is less important than how it is obtained: 1. Consider the x and y motion separately. 2. Find the time of flight from the y-motion 3. Find the x-position at the end of the flight - this is the range. If you remember these steps, you can deal with many variants of the basic problem, such as: a cannon on a hill that fires horizontally (i.e. the second half of the trajectory), a projectile that lands on a hill, or a projectile that must hit a moving target. Horizontal Cannon on a Cliff
A cannonball is fired horizontally from the top of a cliff. The cannon is at height above ground level, and the ball is fired with initial horizontal speed . http://session.masteringphysics.com/myct/assignmentPrint?assignmentID=1114140 Page 2 of 3 MasteringPhysics: Assignment Print View 3/2/08 4:53 PM Part A Assume that the cannon is fired at cannonball at the time Part A.1 ? and that the cannonball hits the ground at time . What is the y position of the Equation of motion in y direction with initial y position of and initial y velocity . The particle has an Suppose that a particle starts at time acceleration ANSWER: in the positive y direction. What is the particle's position at some later time ? = 0 Part A.2 y postition of cannonball ). Given your answer to the previous question, choose the correct equation for the y position of the cannonball at any time before it hits the ground (or ANSWER: = Part A.3 Time at which the ball hits the ground Part not displayed Express the y position of the cannonball in terms of ANSWER: = . The quantities and should not appear in your answer. Part B Given that the projectile lands a distance Part B.1 from the cliff, as shown, find the initial speed of the projectile, . Velocity component in x direction Part not displayed Part B.2 If you are stuck, use as a last resort Part not displayed Express the initial speed in terms of ANSWER: , , and . = Part C What is the y position of the cannonball when it is a distance Part C.1 Velocity component in x direction Part not displayed Hint C.2 Use the initial velocity to get the time Hint not displayed Express the position of the cannonball in terms of ANSWER: = only. from the hill? Summary 2 of 2 items complete (102.6% avg. score) 2.05 of 2 points http://session.masteringphysics.com/myct/assignmentPrint?assignmentID=1114140 Page 3 of 3 ...
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This note was uploaded on 05/08/2008 for the course PHYSICS 2211 taught by Professor Uzer during the Spring '08 term at Georgia Tech.
- Spring '08
- Projectile Motion