Question 1151049
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If "k" is the spring constant, then the potential energy stored is


    P = {{{(1/2)*k*x^2}}},


where "x" is the value of stretching, measured in meters.


In your case


    28 = {{{(1/2)*10*x^2}}}.


Hence,


    {{{x^2}}} = {{{(28*2)/10}}} = 5.6 m^2

    x   = {{{sqrt(5.6)}}} = 2.366 meters (approximately).    <U>ANSWER</U>
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