document.write( "Question 1161025: 3. A bus moving in straight line at a speed of 20 m/s begins to slow down at a constant rate of 3 𝑚/𝑠2 each second. Find how far it goes before stopping? \n" ); document.write( "

Algebra.Com's Answer #784440 by ikleyn(52781) $\"\"$ $\"About$

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document.write( "Again, I will consider the problem as if it comes from Physics.\r\n" );
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document.write( "Then the breaking force is the product of the mass \"m\"  and acceleration \"a\"\r\n" );
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document.write( "          = ma.\r\n" );
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document.write( "while the kinetic energy is  .\r\n" );
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document.write( "Now apply the Energy conservation law: The kinetic energy is equal to the work of the force.\r\n" );
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document.write( "The force is  ,  and its work is the product of the force by the breaking distance \"x\", which is the unknown in this problem.\r\n" );
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document.write( "So you have this equation\r\n" );
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document.write( "     = m*a*x.\r\n" );
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document.write( "Cancel the mass in both side and obtain\r\n" );
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document.write( "    x =  =  =  = 66.666... = 66.7 meters (rounded).\r\n" );
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document.write( "ANSWER.  The breaking distance is  66.7 meters.\r\n" );
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\n" ); document.write( "\n" ); document.write( "The other way to solve the problem is to use Calculus.\r
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