document.write( "Question 532701: An object accelerates at 1 G. How long does it take to reach 90% of the speed of light. (I'm writing a sci-fi) \n" ); document.write( "
Algebra.Com's Answer #350908 by Edwin McCravy(20064)\"\" \"About 
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document.write( "vf = v0 + at\r\n" );
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document.write( "where vf = final velocity\r\n" );
document.write( "and v0 = initial velocity\r\n" );
document.write( "and a = acceleration\r\n" );
document.write( "and t = time in seconds\r\n" );
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document.write( "We solve it for t\r\n" );
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document.write( "at = vf - v0\r\n" );
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document.write( "t = \"%28v%5Bf%5D-v%5B0%5D%29%2Fa\"\r\n" );
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document.write( "The speed of light is 299792458 m/s, 90% of that is 269813212.2 m/s\r\n" );
document.write( "so that will be vf.\r\n" );
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document.write( "We will assume starting from rest so we will use v0 = 0\r\n" );
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document.write( "1 G is the acceleration = 9.81 m/sē,\r\n" );
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document.write( "we substitute in \r\n" );
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document.write( "t = \"%28v%5Bf%5D-v%5B0%5D%29%2Fa\"\r\n" );
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document.write( "t = \"%28269813212.2-0%29%2F9.81\"\r\n" );
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document.write( "t = 27503895.2 seconds = 458398.3 hours = 19099.9 days = 52.3 years.\r\n" );
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document.write( "Edwin
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