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27 Nov 2019

Joe Cool drives to see his girlfriend who attends anothercollege.
(a) The 144 km trip takes 2.0 h. What was the average speed for thetrip?
..... km/h

(b) The return trip over the same route takes 3.0 h because ofheavy traffic. What is the average speed for the return trip?
..... km/h

(c) What is the average speed for the entire trip?
.... km/h

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Casey Durgan
Casey DurganLv2
13 Jan 2019
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Related textbook solutions

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

Related questions

A small boat is headed for a harbor 31 km directly northwest of itscurrent position when it is suddenly engulfed in heavy fog. Thecaptain maintains a compass bearing of northwest and a speed of10.1 km/h relative to the water. The fog lifts 3.0 h later and thecaptain notes that he is now exactly 3.9 km south of theharbor.
(a) What was the average speed of the current during those 3.0h?
(b) In what direction should the boat have been heading to reachits destination along a straight course?
the answer is an angle west of north
(c) What would its travel time have been if it had followed astraight course?

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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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