Enter your Name:   Enter your E-mail Address:  Be sure to write all your answers with the proper number of significant figures and to list the units that go with your answers! 01. A projectile launched from the ground hits a target on the ground several meters away from the launch site. If the projectile hits the target with a speed of 124 m/sec, what was the initial speed with which the projectile was fired? 02. A bullet is fired at a target which is at the same height as the gun from which the bullet was fired. If the bullet takes 0.44 seconds to hit the target, how long did it take for the bullet to reach its maximum height? 03. A military rocket is equipped with thruster engines that allow it to navigate towards its target. These thrusters fight gravity so that the vertical acceleration the projectile experiences is greatly reduced. In addition, the thrusters allow the rocket to accelerate horizontally. Do you expect this rocket to travel on a parabolic path? Why or why not? 04. What one condition must apply before you can use the range equation [Equation (4.9)]? 05. If you double the initial speed of a projectile, what happens to that projectile's range? 06. Suppose you used Equation (4.9) to calculate the range of a projectile. If you were to make another calculation in which you included the effect of air resistance, would the calculated range increase or decrease? Assume that the projectile lands at the height from which it was launched. 07. The y-component of a projectile's velocity is 12.1 m/sec. When the projectile once again passes by the height from which it was launched, what is the y-component of its velocity? 08. Which of the following objects would move in a parabolic path? a. A rock thrown with an angle of 40° relative to the ground b. A jet airplane using its engines in flight c. A rocket in space 09. A projectile is fired with a certain initial velocity from the surface of the earth. If the same projectile were taken to the moon and shot from the surface of the moon with the same initial velocity, would it have a larger, smaller, or identical range? Why? Assume that the projectile lands at the height from which it was launched. 10. An explorer follows these directions: Travel with a constant velocity of 2.1 m/sec at a heading of 120.0 degrees for 1.1 hours, then turn to a heading of 200.0 degrees and travel at the same speed for 2.3 hours. What will the explorer's final displacement be? 11. An archer lies on the ground and lets loose an arrow with an initial velocity of 112 ft/sec at = 40.0°. What is the maximum height that the arrow will reach? 12. What is the range of a gun that fires its bullets with a velocity of 175 m/sec at an angle of 30.0 degrees? Assume that the bullets land at the height from which they were launched. 13. Aimed at an angle of 45 degrees, a cannon has a range of 4,123 feet. What is the initial speed of a cannonball launched from this cannon? Assume that the cannonballs land at the height from which they were launched. 14. A diver is on a hill overlooking a lake. If the hill is 45 feet above the surface of the water and the diver jumps horizontally ( = 0°) with an initial speed of 20.0 ft/sec, how far from the hill will the diver hit the lake? 15. In an archery competition, an archer stands on a hill so that the arrow in her bow is 20.0 meters above the ground and is aimed at an angle of 0 degrees relative to the ground. If the archer is trying to hit a target that lies on the ground 118 m away, with what initial velocity must she launch her arrow? (NOTE: The picture is NOT drawn to scale!)