document.write( "Question 264770: At the instant the traffic light turns green, an automobile that has been waiting at an intersection starts ahead with a constant acceleration of 2.80 m/s^2. At the same instant, a truck, traveling with a constant speed of 14.7 m/s, overtakes and passes the automobile.
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document.write( "How far beyond its starting point does the automobile overtake the truck?
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document.write( "How fast is the automobile traveling when it overtakes the truck? \n" );
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Algebra.Com's Answer #194857 by Alan3354(69443)![]() ![]() You can put this solution on YOUR website! At the instant the traffic light turns green, an automobile that has been waiting at an intersection starts ahead with a constant acceleration of 2.80 m/s^2. At the same instant, a truck, traveling with a constant speed of 14.7 m/s, overtakes and passes the automobile. \n" ); document.write( "How far beyond its starting point does the automobile overtake the truck? \n" ); document.write( "How fast is the automobile traveling when it overtakes the truck? \n" ); document.write( "------------------------ \n" ); document.write( "For the car, s = (at^2)/2 = 3.92t^2 \n" ); document.write( "For the truck, s = 14.7t \n" ); document.write( "-------------- \n" ); document.write( "When the distances are equal 14.7t = 3.92t^2 \n" ); document.write( "3.92t^t - 14.7t = 0 \n" ); document.write( "t = 0 (at the light) \n" ); document.write( "t = 14.7/3.92 = 3.75 seconds \n" ); document.write( "At 3.75 seconds, the auto catches up to the truck. \n" ); document.write( "------------------- \n" ); document.write( "s = 14.7*3.75 = 55.125 meters from the light. \n" ); document.write( "-------- \n" ); document.write( "Auto speed = 3.92*3.75 = 14.7 m/sec when it overtakes the truck \n" ); document.write( " \n" ); document.write( " |