Part A A skateboarder starts up a 1.0-m-high, 30 ramp at a speed of 7.2 m/s....

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Part A A skateboarder starts up a 1.0-m-high, 30 ramp at a speed of 7.2 m/s. The skateboard wheels roll without friction. At the top, she leaves the ramp and sails through the air. How far from the end of the ramp does the skateboarder touch down? Express your answer with the appropriate units. View Available Hint(s) 1= 4.89 H m 0 ? Learning Goal: To practice Tactics Box 4.1 Finding the Acceleration Vector. Suppose an object has an initial velocity v ; at time t; and later, at time tf, has velocity of. The fact that the velocity changes tells us that the object undergoes an acceleration during the time interval At = tf - ti. From the definition of acceleration, a = Vf-vi tf-ti = At' we see that the acceleration vector points in the same direction as the vector Av. This vector is the change in the velocity Av = f - vi, so to know which way the acceleration vector points, we have to perform the vector subtraction of v. This Tactics Box shows how to use vector subtraction to find the acceleration vector. - Below is another motion diagram for an object that moves along a curved path. The dots are separated by equal time intervals and represent the position of the object at five subsequent instants. The vectors U21, 32, 43, and 054 represent the average velocity of the object during the four corresponding time intervals. Draw the velocity vectors-021 and -043 and the acceleration vectors a31 and 53 representing the changes in average velocity of the object during the first two and last two time intervals, respectively. Draw the vectors starting at the appropriate black dots. For the velocity vectors, the starting point, length, and direction will be graded. For the acceleration vectors, the starting point and direction will be graded. + No elements selected V43 V32 V54 The Starship Enterprise returns from warp drive to ordinary space with a forward speed of 59 km/s. To the crew's great surprise, a Klingon ship is 130 km directly ahead, traveling in the same direction at a mere 25 km/s. Without evasive action, the Enterprise will overtake and collide with the Klingons in just about 3.8 s. The Enterprise's computers react instantly to brake the ship. Part A What magnitude acceleration does the Enterprise need to just barely avoid a collision with the Klingon ship? Assume the acceleration is constant. Hint: Draw a position-versus-time graph showing the motions of both the Enterprise and the Klingon ship. Let x0 = Okm be the location of the Enterprise as it returns from warp drive. How do you show graphically the situation in which the collision is "barely avoided"? Once you decide what it looks like graphically, express that situation mathematically. Express your answer to two significant figures and include the appropriate units. a = 8.9 Submit km s Previous Answers Request Answer ? Incorrect; Try Again; 4 attempts remaining Part A A skateboarder starts up a 1.0-m-high, 30 ramp at a speed of 7.2 m/s. The skateboard wheels roll without friction. At the top, she leaves the ramp and sails through the air. How far from the end of the ramp does the skateboarder touch down? Express your answer with the appropriate units. View Available Hint(s) 1= 4.89 H m 0 ? Learning Goal: To practice Tactics Box 4.1 Finding the Acceleration Vector. Suppose an object has an initial velocity v ; at time t; and later, at time tf, has velocity of. The fact that the velocity changes tells us that the object undergoes an acceleration during the time interval At = tf - ti. From the definition of acceleration, a = Vf-vi tf-ti = At' we see that the acceleration vector points in the same direction as the vector Av. This vector is the change in the velocity Av = f - vi, so to know which way the acceleration vector points, we have to perform the vector subtraction of v. This Tactics Box shows how to use vector subtraction to find the acceleration vector. - Below is another motion diagram for an object that moves along a curved path. The dots are separated by equal time intervals and represent the position of the object at five subsequent instants. The vectors U21, 32, 43, and 054 represent the average velocity of the object during the four corresponding time intervals. Draw the velocity vectors-021 and -043 and the acceleration vectors a31 and 53 representing the changes in average velocity of the object during the first two and last two time intervals, respectively. Draw the vectors starting at the appropriate black dots. For the velocity vectors, the starting point, length, and direction will be graded. For the acceleration vectors, the starting point and direction will be graded. + No elements selected V43 V32 V54 The Starship Enterprise returns from warp drive to ordinary space with a forward speed of 59 km/s. To the crew's great surprise, a Klingon ship is 130 km directly ahead, traveling in the same direction at a mere 25 km/s. Without evasive action, the Enterprise will overtake and collide with the Klingons in just about 3.8 s. The Enterprise's computers react instantly to brake the ship. Part A What magnitude acceleration does the Enterprise need to just barely avoid a collision with the Klingon ship? Assume the acceleration is constant. Hint: Draw a position-versus-time graph showing the motions of both the Enterprise and the Klingon ship. Let x0 = Okm be the location of the Enterprise as it returns from warp drive. How do you show graphically the situation in which the collision is "barely avoided"? Once you decide what it looks like graphically, express that situation mathematically. Express your answer to two significant figures and include the appropriate units. a = 8.9 Submit km s Previous Answers Request Answer ? Incorrect; Try Again; 4 attempts remaining