Question 673595

The stopping distance (D) of a vehicle varies directly as the square of its velocity (V).  If a vehicle traveling 40 mph requires 100 feet to come to a stop, find the stopping distance of a vehicle traveling 60 mph.


Since the stopping distance varies directly as the square of its velocity (V), then:


{{{D = kV^2}}}, with k being the constant of variation 


{{{100 = k40^2}}}

 
100 = 1,600k


k = {{{100/1600}}}, or {{{1/16}}}


{{{D = kV^2}}}

 
{{{D = (1/16) * 60^2}}} 


{{{D = (1/16) * 3600}}}


D, or stopping distance = {{{highlight_green(225)}}} ft


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