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An athlete wants to run a 1500m race with an average velocity of 6.00 m/s. After running the first 500m, he notices that the time elapsed is 100 seconds. Panicking, he accelerates for “t” seconds at 0.2 m/seconds^2 and finishes the race at his new faster speed. He makes it just in time. How long did he accelerate for? (Use 5 significant figures in the answer)

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Jarrod Robel
Jarrod RobelLv2
7 Mar 2019

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Related textbook solutions

Physics: Principles with Applications
7th Edition, 2013
Giancoli
ISBN: 9780321625922

Related questions

Clear the Runway

To take off from the ground, an airplane must reach a sufficiently high speed. The velocity required for the takeoff, the takeoff velocity, depends on several factors, including the weight of the aircraft and the wind velocity.

(a) A plane accelerates from rest at a constant rate of 5.00 m/s2 along a runway that is 1800 m long. Assume that the plane reaches the required takeoff velocity at the end of the runway. What is the time t needed to take off?

Express your answer in seconds using three significant figures.

(b) What is the speed vTO of the plane as it takes off?

Express your answer numerically in meters per second using three significant figures.

(c) What is the distance dfirst traveled by plane in the first second of its run?

Express your answer numerically in meters using three significant figures.

(d) What is the distance dlast traveled by plane in the last second before taking off?

Express your answer numerically in meters using three significant figures.

(e) What percentage of the takeoff velocity did the plane gain when it reached the midpoint of the runway?

Express your answer numerically to the nearest percent.

vf = vi + at
rx = vit + ½ at2
vf2 = vi2 +2arx
rx = ½ (vi + vf)t

4. A sailboat is moving across the water at 3.0 m/s. A gust of windfills its sails and it accelerates at a constant 2.0 m/s2. At thesame instant, a motorboat at rest starts its engines andaccelerates at 4.0 m/s2. After 3.0 seconds have elapsed, find thevelocity of (a) the sailboat, and (b) the motorboat.



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19. The United States and South Korean soccer teams are playing inthe first round of the World Cup. An American kicks the ball,giving it an initial velocity of 3.6 m/s. The ball rolls a distanceof 5.0 m and is then intercepted by a South Korean player. If theball accelerates at -0.50 m/s2 while rolling along the grass, findits velocity at the time of interception.




23. The city is trying to figure out how long the traffic lightshould stay yellow at an intersection. The speed limit on the roadis 45.0 km/h and the intersection is 23.0 m wide. A car istraveling at the speed limit in the positive direction and canbrake with an acceleration of -5.20 m/s2. (a) If the car is to stopon the white line, before entering the intersection, what is theminimum distance from the line at which the driver must apply thebrakes?



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I no this is alot of questions but im having trouble answeringthese! So please help me..

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